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Answer:

At standard temperature and pressure (STP), two atoms of the element bind to form dioxygen, a colorless, odorless, tasteless diatomic gas with the formula O2. Oxygen is a member of the chalcogen group on the periodic table and is a highly reactive nonmetallic element.

Answer:

Oxygen is a colorless, odorless, tasteless gas. It changes from a gas to a liquid at a temperature of -182.96°C (-297.33°F). The liquid formed has a slightly bluish color to it. Liquid oxygen can then be solidified or frozen at a temperature of -218.4°C (-361.2°F).

Explanation:

The theoretical yield of iron metal : 16.418 g

A reaction coefficient is a number in the chemical formula of a substance involved in the reaction equation. The reaction coefficient is useful for equalizing reagents and products.

Reaction

2 Fe₂O₃ + 3 C ⇒ 4 Fe + 3 CO₂

mol Fe₂O₃ (MW=159,69 g/mol) :

[tex]\tt \dfrac{23.5}{159.69}=0.147[/tex]

mol  Fe₂O₃ : mol Fe = 2 : 4

mol Fe :

[tex]\tt \dfrac{4}{2}\times 0.147=0.294[/tex]

mass Fe(the theoretical yield) :

[tex]\tt 0.294\times 55.845~g/mol=16.418~g[/tex]

Answer:

The correct answer with signfigs is 16.4 for the first part

The second box is 88.4

Explanation:

Answer: The bus traveling 200km in 6 hours is traveling the fastest.

Explanation:

Bus 1

150km/5hrs

Simplify -> 30km/hr

Bus 2

200km/6hrs

Simplify -> About 33.333km/hr

Answer:

[OH⁻] = 8.91x10⁻¹²M

Explanation:

In aqueous solutions, the [OH] and [H⁺] are associated in the equation of hydrolisis of water:

1x10⁻¹⁴ = [OH⁻] [H⁺]

With pH, we can solve for [H⁺] and obtain, the [OH⁻] using this equation:

pH = -log [H⁺]

[H⁺]= 10^-pH

[H⁺] = 1.122x10⁻³M

1x10⁻¹⁴ = [OH⁻] [1.122x10⁻³M]

D. MgO + 2HCI – MgCl2 + H20

The chemical equation is said to be balanced if the number of atoms in the reactants is equal to the number of atoms in the product

A. CaO2 + HCl → CaCl2 + H20

atoms O, Cl and H are not the same

B. CO2 + H2O + H2CO2

atoms O are not the same

C. K+ H2O → K20 + H2

atoms K are not the same

D. MgO + 2HCI – MgCl2 + H20

Mg, left = 1, right=1

O, left=1, right=1

H, left=2, right=2

Cl, left=2, right=2

Chemical equation is balanced

Answer:

B. CO2 + H2O + H2CO2

Explanation:

Answer:

Ionic bonds - an intramolecular force exist in a nonmetal and metal compounds such as NaCl. The Na donate 1 electon to Cl to complete its octet rule.

Covalent bond - an intramolecular force exist in a nonmetal and nonmetal compounds such as bonds O2, Cl2, CO2, sugar, proteins and most of organic compounds and biomolecules by sharing electrons to bond.

There are two types of covalent bonds: polar and nonpolar. Polar bond is a bond between two different nonmetal atoms of different electronegativities. While nonpolar bond is a bond between the same atom or two differenct atoms of the same electronegativities (if there is). Their electronegativities pull will cancel so that their overall polarity is zero.

Answer: The atmosphere of Earth wasn't always full of oxygen. ... An accidental mutation would some day change the world forever as these organisms would become able to feed off of the sunlight around them, and produce oxygen in a process known as photosynthesis. This oxygen, which none of these organisms could use, was toxic.

Answer: In order to help the plants reproduce, flowers that are bright in color are meant to attract birds, bees and other insects. In the genetics of a flower, bright or dull colors are set in

Explanation:

Answer:

3 sulphur is more electrically –

Answer:

Explanation:

The volume of a substance when given the density and mass can be found by using the formula

[tex]volume = \frac{mass}{density} \\ [/tex]

From the question we have

[tex]volume = \frac{25}{9.1} \\ = 2.747252...[/tex]

We have the final answer as

Hope this helps you

Answer:

It would be a physical change, because the atoms are rerranging to form new molecules!

Explanation:

Answer:

Actual yield = 20.03g

Explanation:

[tex]% yield = 100.\frac{actual yield}{theoretical yield}[/tex]% [tex]yield[/tex] = [tex]100. \frac{actual \ yield}{theoretical \ yield}[/tex]

Actual yield = % yield.(theoretical yield) / 100

Actual yield = 75.26.7/100

Actual yield = 20.025

Answer: I got 20.025 and then I rounded it to 20.0

Explanation:

Answer:

mass number

Explanation:

The sum of the protons and neutrons in an atom equals the mass number of such an atom.

So;

Mass number = number of protons + number of neutrons.

Answer:

82

Explanation:

i took the assingment

Answer:

The heat capacity and the specific heat are related by C=cm or c=C/m. The mass m, specific heat c, change in temperature ΔT, and heat added (or subtracted) Q are related by the equation: Q=mcΔT. Values of specific heat are dependent on the properties and phase of a given substance.

Explanation:

Answer:

23.2 degrees c

Explanation:

Answer:

The initial temperature of the metal is 84.149 °C.

Explanation:

The heat lost by the metal will be equivalent to the heat gain by the water.  

- (msΔT)metal = (msΔT)water

-32.5 grams × 0.365 J/g°C × ΔT = 105.3 grams × 4.18 J/g °C × (17.3 -15.4)°C

-ΔT = 836.29/12.51 °C

-ΔT = 66.89 °C

-(T final - T initial) = 66.89 °C

T initial = 66.89 °C + T final

T initial = 66.89 °C + 17.3 °C

T initial = 84.149 °C.

Vertical Column is a group

Horizontal is Period

Aliki earth metals is a group

Lithium- Neon is both

Based on electrons are both

Number of electron shells is both

Answer:

the zinc strip begins to darken. If left in the solution for a longer period of time, the zinc will gradually decay due to oxidation to zinc ions.

Explanation:

Answer:

B

Explanation:

I did it

Neither physical not chemical changes alter the atomic structure of a substance. The correct option is b.

When one chemical substance is transformed into one or more different substances, such as when iron becomes rust, a chemical change occurs.

Chemical changes occur as a result of chemical reactions, and the resulting substances have different properties due to the different arrangements of their atoms and molecules.

Physical changes affect a chemical substance's form but not its chemical composition.

Physical changes can be used to separate mixtures into their component compounds, but not to separate compounds into chemical elements or simpler compounds.

Physical or chemical changes have no effect on a substance's atomic structure.

Thus, the correct option is b.

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Answer:

its weight

Explanation:

mass is how much space it takes up the volume stays the same density is what happens after so its weight

Answer:

10.99s

Explanation:

Given parameters:

Speed of the fly = 9.1m/s

Distance flown = 100m

Unknown:

Time taken to fly this distance = ?

Solution:

Speed is distance divided by the time;

  Mathematically;

            Speed  = [tex]\frac{distance}{time}[/tex]  

             Time  = [tex]\frac{distance}{speed }[/tex]  

Insert the parameters and solve;

        Time  = [tex]\frac{100}{9.1}[/tex]   = 10.99s

Answer:

I think it's the last one I'm sorry if it's wrong

Explanation:

it sounds like it fits

Answer:

New volume V2 = 120.4 ml

Explanation:

Given:

Pressure P1 = 1.12 atm

New pressure P2 = 1.12[1+0.25] = 1.4 atm

Old volume V1 = 150.5 ml

Find:

New volume V2

Computation:

P1V1 = P2V2

(1.12)(150.5) = (1.4)(V2)

V2 = 120.4 ml

New volume V2 = 120.4 ml

The layers of the earth were formed due to the sediments that significantly flattens out beside the center of the earth. After a long duration, a new layer is spread over the older layer, and so on.

The different layers of the earth are as follows:

The above-mentioned layers of the earth were formed with the impact of the building blocks of the earth that are remarkably known as Planetesimals, collided, and collapsed.

During that time, the hardest elements like nickel, iron, etc. constitute the core while the lighter elements like carbon, oxygen, silicon, etc. play an essential role in the formation of crust and mantle.

Therefore, the layers of the earth were formed due to the sediments that significantly flattens out beside the center of the earth.

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Answer:

igneous rock

Explanation:

Explanation:

A and D. the answer is a and d

Answer:

2 1 4 3

Explanation:

Polar solute dissolve in polar solvent and non polar solute dissolve in non polar solvent. Therefore the order of solubility is calcium bromide> calcium chloride>calcium bicarbonate>calcium carbonate.

Solubility shows the extent of solubility of a solute in solvent to make a solution. Solute is substances that is present in small amount. solvent is a substance that is present in large amount. Its SI unit is gram per liter or g/L.

Bond strength affect the solubility of a solute in solvent. weaker the bond strength is, more the solubility is. The weaker bond can be easily broken by water molecule

Calcium bromide is more soluble than calcium chloride as the bond strength in calcium bromide is weaker than calcium chloride. Calcium bicarbonate is more soluble than calcium carbonate.

Therefore the order of solubility is calcium bromide> calcium chloride>calcium bicarbonate>calcium carbonate.

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Answer:

it is number 2

Explanation:

hope this helps it is number 11

The atomic mass number tells us the number of neutrons and protons in the nucleus of an atom.