the number of protons in an uncharged atom group of answer choices determines the mass number determines the number of isotopes equals the number of electrons in the outer orbital of the atom equals the number of electrons

Ions can conduct electricity during electrolysis because they are free to move and they are charged. Hence, the delocalization of ions and electrons conduct electricity.

Electrolytes are molten compounds or solution which can conduct electricity due to the presence of free ions in the solution. Neutral atoms when lose or gain electrons, they acquire a charge and become ions.

The mobility of charged particles causes the electrical current. Thus, ions and electrons in a solution which are free to move are conducting. In solid state, these ions are held by strong intermolecular forces.

Hence, they are not free to move in solid state. But in the molten state, they are free to move and conduct electricity.

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This fire pit would be 1.6 * 10³ years old, based on the supplied statement.

Metal smelting makes use of dirty carbon in the shape of coke made from coal and charcoal made from wood. It is crucial for the steel and iron industries in particular. Electric drive brushes, furnaces linings, etc pencils all make use of carbon. Processes for filtration and purification use chemical..

We must determine how long the charcoal sample has been deteriorating in order to determine its age:

[tex]$$\begin{gathered}t=\frac{1}{\lambda} \cdot \ln \left(\frac{R_0}{R}\right) \\\lambda=\frac{\ln 2}{T_{1 / 2}}\end{gathered}$$[/tex]

Combined we get.

[tex]$$t=\frac{5730 \text { year }}{\ln 2} \cdot \ln \left(\frac{\frac{15}{1}}{\frac{63}{5}}\right)$$[/tex]

Finally:

[tex]$$t=1.6 \cdot 10^3 \text { year }$$[/tex]

Result

[tex]$$t=1.6 \cdot 10^3 \text { years }$$[/tex]

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Answer:

potassium (K) has (220 pm) while Sodium (Na) has (180 pm). The potassium atom has an extra electron shell compared to the sodium atom thus the potassium has a larger atomic radius.

Based on the periodic table, the element that is most reactive is Na.

The correct option is A.

Reactivity is a gauge of an element's propensity to create compounds with other elements. While certain elements require energy to react and are inert, others will do so simply and spontaneously. Reactivity is a gauge of an element's propensity to create compounds with other elements.

Reactive elements are the Group 1 and Group 2 metals. Also, the Group 17 and Group 16 non-metals are reactive non-metals.

Group 1 and Group 2 metals form positive ions easily by electron loss. Group 17 and Group 16 non-metals form negative ions by electron gain.

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Answer:

A silvery-white metal that ignites easily in air and burns with a bright light.

Oxygen: When exposed to oxygen, magnesium turns into magnesium oxide. Hydrogen: When exposed to hydrogen, magnesium turns into magnesium hydride. Nitrogen: When reacted with nitrogen, magnesium turns into magnesium nitride.

Explanation:

The fill in the blanks for the thermodynamic parameters is given as follows  :

a) Standard

b) atm

c) M

a) Thermodynamic parameters are the usually calculated for the compounds under the standard conditions.

b) Since the are values tend to vary somewhat with the conditions. To be in this state. A gas must have the pressure of 1 atm.

c) And a solution must have the concentration of the 1 M.

Some of the thermodynamic parameters are as follows :

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While dissolving 92.0 grams of CH3CH2OH, ethanol, in 270. g of water.  7.41 mol/kg, is the molality of ethanol in the solution.

To determine the molality of ethanol in the solution, we need to first find the number of moles of ethanol and then divide that by the number of kg of water.

To find the moles of ethanol, we can use the formula:

Mass of ethanol divided by its molar mass yields moles of ethanol.

moles of ethanol = (92.0 g) / (46.07 g/mol) = 2.00 moles

To find the number of kg of water, we can convert the mass of water from grams to kg using the conversion factor 1 kg = 1000 g:

mass of water in kg = (270. g) / (1000 g/kg) = 0.270 kg

Now, we can calculate the molality of ethanol in the solution using the formula:

molality = 2.00 moles / 0.270 kg = 7.41 mol/kg

The molality of ethanol in the solution is 7.41 mol/kg.

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Answer:

16Ag +S8 --> 8Ag2S

Explanation:

You know that you are starting out with 8 sulfer's on the reactant side, so there must be an equal amount on the product side. So, to get 8 sulfer's on the product side we multiply the entire (Ag2S) by 8 to get 8Ag2S. Now on the reactant and product side we have an equal amount of sulfer. However, the product side has 16 silvers. To balance this out, on the reactant side we multiply the number of Ag by 16 to get 16 Ag ont he reactant and product sides. Now the reactant and product sides have the same number of each element :)

A spontaneous process is a kind of process which occurs without any external input to the system. Earth moves around the sun and formation of solid sodium chloride from sodium metal and chlorine gas.

A spontaneous process is a process which is in one direction under a certain set of conditions and a nonspontaneous process is in the reverse direction. For instance, At room temperature and atmospheric pressure ice will melt spontaneously, but water will not freeze spontaneously.

Boiling always occur spontaneously at all the given temperatures.

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The  two observations about temperature and salinity on the Caribbean and Pacific sides of Panama are:

Observation #1: The Caribbean side of Panama generally has higher temperatures than the Pacific side due to its location closer to the equator. The Caribbean coast of Panama is generally hotter and more humid than the Pacific side. Additionally, trade winds blowing from east to west across the Caribbean Sea can bring warm and humid air to the Caribbean coast of Panama.

Note that Observation #2: The Pacific side of Panama generally has higher salinity levels than the Caribbean side. This is because the Pacific Ocean is saltier than the Caribbean Sea, due to the fact that the Pacific Ocean has a larger surface area and receives less freshwater from rivers. Additionally, the Panama Canal, which connects the Pacific and Caribbean, allows for a mix of water between the two bodies of water, but the Pacific water is saltier and more dense and the effect of the canal is to reduce the salinity of the Caribbean.

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4.01 x 1012 grammes of beryllium contain 4.45 x 1011 moles of beryllium. The chemical element beryllium has the atomic number 4 and the letter Be assigned to it. Alkaline earth metal is brittle, steel-gray, strong, and light.

The formula: can be used to determine how many moles of a material there are.

Molar mass divided by mass equals a mole.

Beryllium has a molar mass of 9.012 g/mol.

Therefore, we can perform the following calculation to determine how many moles of beryllium there are in 4.01 x 1012 grammes of beryllium:

4.01 x 10-12 grammes are equal to 9.012 grammes per mole.

4.45 x 1011 moles are one mole.

Therefore, 4.01 x 1012 grammes of eryllium contain 4.45 x 1011 moles of eryllium.

Note that both numbers must have the same exponent when writing in scientific notation, and that you must use a calculator to perform the calculation if you don't want to receive the wrong answer.

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you decide to test your pillbugs' preference for an acidic environment versus a nonacidic environment. on one side of the chamber you place filter paper moistened with water. Dry filter paper is appropriate to place on the other side to test this variable.

Armadillidiidae (Pillbugs) is a family of woodlice, a terrestrial crustacean group in the order Isopoda. Unlike members of some other woodlice families, members of this family can roll into a ball, an ability they share with the outwardly similar but unrelated pill millipedes and other animals. This ability gives woodlice in this family their common names of pill bugs or roly polies.Other common names include slaters, potato bugs, and doodle bugs. Most species are native to the Mediterranean Basin, while a few species have wider European distributions. The best-known species, Armadillidium vulgare, was introduced to New England in the early 19th century and has become widespread throughout North America.

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Kp is the equilibrium constant for a reaction in terms of partial pressures. And Kp = 32.6 (8.314 J/mol·K)^(-4) (359+273)K.

While Kc is the equilibrium constant for a reaction in terms of concentrations. To convert between Kp and Kc, the ideal gas law must be used. The ideal gas law is PV = nRT, where P is the pressure, V is the volume, n is the number of moles, R is the ideal gas constant, and T is the temperature in Kelvin.

Given the reaction,

3A(g)+3B(g)⇌C(g)

We can convert Kc to Kp by using the following relationship:

Kp = Kc(RT)^(Δn)

where Δn is the change in the number of moles of gas between products and reactants.

In this case, Δn = 1 - (3+3) = -4,

Kp = 32.6 (8.314 J/mol·K)^(-4) (359+273)K

Kp value can be calculated by inserting the given values in above equation. It is important to note that the units of R and T must be consistent with the units used for Kc. In summary, to find Kp, we need to know Kc, the change in the number of moles of gas between products and reactants and the temperature in Kelvin.

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According to the table the density of water is 1g/cm^3 and the density of saturated solution is 1.12g/cm^3.

The ratio of an object or substance's volume (the amount of space it occupies) to the amount of matter it contains is known as its density (its mass). Density Formula: ρ = m/V, where ρ is the density, m is the object's mass, and V is its volume.

Given the volume of water = 50ml

The mass of water = 50g

Then density of water = mass of water/volume of water = 50/50 = 1g/ml = 1g/cm^3

The mass of Saturated Salt Solution = 56g

The volume of Saturated Salt Solution = 50ml

The density of Saturated Salt Solution = 56/50 = 1.12g/ml = 1.12g/cm^3

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complete question: Calculate the densities of the liquids in Table 2.3. The accepted density of water is 1 g/cm3. How do your results compare? Remember that 1 cm3 = 1 mL

When a substance changes from a solid to a liquid, it is undergoing a process called melting. During this process, energy is added to the substance in the form of heat. This energy causes the bonds between the atoms or molecules in the solid to break, allowing them to move freely and take on the characteristics of a liquid.

We can understand by many ways such as when a substance changes from a liquid to a gas, it is undergoing a process called vaporization or boiling. During this process, energy is added to the substance in the form of heat. This energy causes the bonds between the atoms or molecules in the liquid to break, allowing them to move freely and take on the characteristics of a gas.

When a substance changes from a gas to a liquid or a solid, it is undergoing a process called condensation or solidification. During this process, energy is removed from the substance in the form of heat. This energy causes the atoms or molecules in the gas to lose their kinetic energy, slowing down their movement and allowing them to bind together, taking on the characteristics of a liquid or a solid.

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The Correct Question is:-

What will be the reaction when we change any substance from solid to liquid  gas?

3. 10 x 1023 molecules of F2 have a mass in grammes of 1.178 x 1025. A body's mass is an inherent quality. Prior to the discovery of the atom and particle physics,

It is possible to get the mass in grammes of 3.10 x 1023 molecules of F2 by applying the following formula:

Number of molecules times molar mass (in g/mol) equals mass (in grammes).

Since F2 has a molar mass of 38.00 g/mol, its mass in grammes is calculated as follows: mass = 3.10 x 1023 x 38.00 = 1.178 x 1025 grammes.

The amount of matter in a particle or object is represented by the dimensionless quantity mass (symbolised m). The kilogramme is the International System's (SI) preferred unit of mass (kg). mass. [ măs ] a measurement of how much matter is present in or makes up a physical body.

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The density of isopropyl alcohol is 0.785 g/mL. 22volume, in milliliters, of isopropyl alcohol should be dispensed.

What is density ?

Mass per unit volume of a solid substance; density. Density is defined as d = M/V, where M stands for mass, and V for volume. The unit of density that is most frequently used is grams per cubic centimeter.

What is isopropyl alcohol?

Common names for isopropyl alcohol include "isopropanol," "n-propanol," and "dimethylcarbinol." It is a colorless, flammable liquid with the chemical formula C3H8O.

Therefore,  density of isopropyl alcohol is 0.785 g/mL. 22volume, in milliliters, of isopropyl alcohol should be dispensed.

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You can determine if two substances have the same melting point by comparing their physical properties, such as density and solubility.

You can determine if two substances have the same melting point without using any form of spectroscopy by comparing their physical properties, such as density, solubility, and boiling point. Additionally, you can use a microscope to compare the two substances under high magnification. If the two substances have the same physical properties, they will likely have the same melting point. If they differ, it could indicate that the melting points are not the same. By comparing the two substances to one another, you can determine if they have the same melting point without the need for any kind of spectroscopy.

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If the substances have the same melting point we can determine if they are the same with the determination of shift in the melting point without using any form of spectroscopy.

Melting point of a substance can be defined as the temperature at which a substance changes its state from solid to liquid. The melting point the solid and liquid phase exist in equilibrium. The melting point is said to be the temperature at which a solid changes into a liquid. The study of Spectroscopy is the field that measures and interprets the electromagnetic spectra that result from the interaction between electromagnetic radiation and matter as a function of the wavelength or frequency of the radiation. It is the study of the absorption and emission of light and other radiation by matter. Spectroscopy involves the splitting of light into its constituent wavelengths which is done in the same way as a prism splits light into a rainbow of colors.

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This is an example of a phase transition, which is a change in the physical state of a substance, such as a solid, liquid, or gas, due to changes in temperature and/or pressure.

In this case, the phase transition is from graphite, a form of carbon in a solid state, to diamond, another form of carbon in a solid state, under high temperatures and pressures.

Graphite and diamond are both forms of carbon, but they have different crystal structures, which gives them distinct properties. Graphite is a soft, slippery solid that is used as a lubricant and in pencils because of its ability to leave a dark mark on the paper. Diamond, on the other hand, is the hardest natural substance known and is used in cutting tools and jewelry.

The change from graphite to diamond is a phase transition, which occurs when the temperature and pressure of a substance are increased beyond certain limits. The exact conditions required to transform graphite into diamond vary depending on the specific method used but typically involve temperatures of around 900-1300 degrees Celsius and pressures of around 50,000 atmospheres. This process is called as high-pressure high temperature (HPHT) method. The process of graphite to diamond is known as metamorphism.

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If 53 grams of magnesium oxide reacts with an excess amount of sodium chloride there would be  125.18 g magnesium chloride

The limiting reactant is magnesium oxide since NaCl is in excess, which MgO has a mass of 53.00 grams.

MgO  molar mass is  40.31 g/mol.

MgCl₂'s molar mass is95.211 g/mol

The equation with a balance reaction

2NaCl + MgO → Na2O + MgCl₂

We should determine the moles of MgO

Mass MgO divided by molar mass MgO yields moles of sodium chloride.

moles of MgO  = mass/ molar mass

moles of MgO = 53 grams / 40.31 g/mol

moles of MgO =  1.3148 moles

Calculate the moles of Na₂O

MgO is the limiting reactant.

To make 1 mol of Na₂O and 1 mol of MgCl₂ we need 2 moles of NaCl, we require 1 mol of MgO.

with unitary method we can calculate the moles of Na₂O

moles of MgCl₂ = 1/1 x moles of MgO

Moles of MgCl₂ = 1.3148 moles

Then calculate the mass of Na₂O

MgCl₂ molar mass is equal to its molecular weight times moles

mass MgCl₂  = 1.3148 moles* 95.211 g/mol. = 125.18 g

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The salt that would lower the freezing point of water the most is sodium chloride.

Sodium chloride is the most effective salt at decreasing the freezing point of water. This is because sodium chloride has the highest solubility of all the salts, meaning that it can dissolve and form a solution with a higher concentration of solute. This leads to a decrease in the freezing point of water, as the solute molecules interfere with the structure of the water molecules and prevent them from forming an orderly pattern. Other salts, like potassium chloride, magnesium sulfate, and calcium chloride, may still lower the freezing point of water, but to a lesser degree compared to sodium chloride.

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Calcium chloride is the salt which lower the freezing point of water the most.

The freezing point can be defined as the is the exact temperature at which a liquid becomes a solid. The freezing point of water is 32 degrees Fahrenheit. Freezing point describes the moment of transition much as the melting point captures the moment when ice turns from a solid to a liquid. Normal fresh water freezes at 32 degrees Fahrenheit and seawater freezes at about 28.4 degrees Fahrenheit because of the salt in it. Calcium chloride is highly soluble in water. It lowers the freezing point of water the most. Both calcium chloride and magnesium chloride have lower the freezing points. When calcium chloride comes in contact with ice, it rapidly lowers the freezing point of water and melts snow and ice quickly. Calcium chloride forms brine faster than other salts because of its hygroscopic properties.

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The complete question is,

Assuming all the salts below are the same concentration, which salt would lower the freezing point of water the most?

(a) magnesium chloride

(b) calcium chloride

(c) sodium chloride

Answer:

chromosome

Explanation:

Answer: Chromosome

Explanation: A chromosome is made up of a single, massively long DNA molecule containing a linear array of many genes.

a. In scientific notation, 48,000,000,000 g is written as 4.8 x 1010 g.

b. The scientific notation for 48 x 109 g is already there.

c. 4.8 x 10-9 g is how 48 x 10-10 g is written in scientific notation.

A number is expressed in scientific notation by a coefficient, which is a number between 1 and 10, multiplied by a power of 10. How many times the coefficient must be multiplied by 10 to obtain the original value is indicated by the exponent on the 10.

In case a, the exponent is 10, the coefficient is 4.8, and the result is 4.8 x 1010 = 48,000,000,000.

In case b, the exponent is nine and the coefficient is 48, hence 48 x 109 = 48 x 1000000000 = 48,000,000,000

In C, the exponent is -9 and the coefficient is 4.8, thus 48 x 10-10 = 48 x 0.0000000001 = 0.00000048 is the result.

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The best safety practice that is recommended before leaving the chemistry laboratory is that remove the lab coat,  the goggles and the gloves and wash the hands properly.

The  best safety practice that is recommended before leaving the chemistry laboratory are :

These are the some basic safety practices that is recommended to follow before leaving the chemistry laboratory. Wash the exposed areas. Most of chemicals are toxic , so clean it properly before leaving the lab.

This question is incomplete, the complete question is :

what is the best safety practice recommended before leaving the chemistry laboratory? group of answer choices :

1) remove lab coat

2)  remove goggles and the gloves

3) wash the hands properly.

4) none of the above

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Your friend is studying a specific exergonic reaction. Your friend hypothesizes that the addition of enzyme X will reduce the delta-G of this reaction, thus allowing it to proceed spontaneously.

Enzymes do not change delta-G, so this hypothesis does not fit with what is known about this reaction.

According to the second law of thermodynamics any reaction that occurs at constant temperature without input of electrical energy or photons is exergonic. An example is cellular respiration. An exergonic reaction is a chemical reaction in which the change in free energy is negative (there is a net loss of free energy). It shows a spontaneous reaction if the system is closed and the initial and final temperatures are the same. For processes that take place in a closed system at constant pressure and temperature, the Gibbs free energy is used, while the Helmholtz energy is relevant for processes that take place at constant temperature and volume.

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Your friend is studying a specific exergonic reaction. your friend hypothesizes that the addition of enzyme x will reduce the delta-g of this reaction, thus allowing it to proceed spontaneously. The hypothesis does not fit with what is known about this reaction because Enzymes do not change delta-G.

1) An exergonic reaction is a reaction that produces free energy. Because it releases energy rather than consuming it, this kind of reaction can occur naturally, unhindered by outside factors.

2) Chemical processes known as exergonic reactions have a negative change in free energy. The free energy of a system is used to calculate its overall quantity of available energy; negative changes signify energy release, whilst positive changes signify energy storage.

Only the activation energy is altered by enzyme.

This concept does not make sense given what is known about the reaction because enzymes do not alter delta G.

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Metal reactivity increases down groups and declines across periods from left to right.

because metals' reactivity increases as they move along the group. Since they are farther from the nucleus and have greater shielding, which results in a lower nuclear attraction, the outer electrons are simpler to expel.

Ionization Energy, which measures how easily an element may expel its electrons, is one influencing factor. The element's electronegativity is another consideration since it affects how eagerly an element seeks out electrons from other elements.

As you move throughout a period from left to right, responsiveness declines. It is easier for electrons to be given or taken away the further to the left and down the periodic chart you travel, leading to higher reactivity.

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If 8. 4 L of hydrogen gas and 18. 1 g of silicon tetrachloride react (at STP), the mass of silicon that will precipitate out is 2.98 g.

The reaction between silicon tetrachloride (SiCl4) and hydrogen gas (H2) is as follows:

SiCl4 + 2H2 -> Si + 4HCl

The balanced equation can be used to calculate the stoichiometry of the reaction. The ratio of SiCl4 to Si is 1:1, and the ratio of H2 to HCl is 2:4.

From the information given, we know that 18.1 of SiCl4 reacts with 8.4 L of H2 at STP. To determine the number of moles of SiCl4, we can use the molar mass of SiCl4, which is 169.89 g/mol.

18.1 g / 169.89 g/mol = 0.106 mol

Since the stoichiometry ratio between SiCl4 and Si is 1:1, we can assume that 0.106 mol of SiCl4 will produce 0.106 mol of Si.

To find the mass of Si that will precipitate out we need to find the molar mass of Silicon, which is 28.0855 g/mol.

0.106 mol * 28.0855 g/mol = 2.98 g

So the mass of silicon that will precipitate out is 2.98 g.

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In a sample of hydrogen iodide, in addition to dispersion forces, dipole-dipole forces also exist.

Intermolecular forces, which act between atoms and various surrounding particles in the form of electromagnetic forces of attraction or repulsion, are one illustration. The three fundamental types of intermolecular interactions are dipole-dipole interactions, London dispersion forces, also known as van der Waals forces, and hydrogen bonds.

As there is a significant difference in electronegativity between the H and I in hydrogen iodide, dipole-dipole interactions will occur.

Iodine is not sufficiently electronegative and is too big for the molecule HI to establish hydrogen bonds, which prevents the formation of hydrogen bonds.

The electrons are dispersed symmetrically with respect to the nucleus due to the action of London dispersion forces between atoms and molecules that are typically symmetric. To the van der Waals forces they belong.

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An empty graduated cylinder is weighs 55.5 g. when filled with the 71.5 ml of  unknown liquid, it weighs 135.0 g. The density of the unknown liquid in g/ml is 29.5 g/L.

The given data :

The mass of empty graduated cylinder = 55.5 g

The volume of the unknown liquid = 50 mL

The mass after the liquid is filled = 135 g

The mass of the liquid = total mass - mass of cylinder

                                      = 135 - 55.5

                                       = 79.5 g

The density is given as :

Density = mass / volume

             = 79.5 / 50

             = 29.5 g/ml

Thus, the density is 29.5 g/L.

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Answer:

7.52x10^24 molecules of H2O.

Explanation:

1)  We need to start with a balanced equation for this reaction, combustion of methane:

CH4 + 2O2 →CO2 + 2H2O

This tells us that 1 mole of methane will produce 2 moles of water.  (2 moles H2O)/(1 mole CH4)

2)  Find the moles of methane in 100g of the molecule.  The molar mass of methane is 16.0 g/mole.  

Moles CH4 = (100g/16.0 g/mole) = 6.25 moles CH4

3)  Multiply 6.25 moles CH4 by the molar ratio from (1):

   (6.25 moles CH4)( (2 moles H2O)/(1 mole CH4) = 12.50 moles H2O [the moles CH4 cancel]

4)  Multiply the moles H2O by Avogadro's number:  6.02x10^23 molecules/mole

   (12.50 moles H2O)*(6.02x10^23 molecules/mole) = 7.52x10^24 molecules of H2O.