Which force keeps the planets from floating off into space?

Earth’s gravity
the Sun’s gravity
the moon’s gravity
Milky Way’s gravity

The molality of a solution : 0.128 m

Given

15.9 g of Ca3(PO4)2 in 400 grams of water.

Required

The molality

Solution

molality = mol solute / kg solvent

solute= Ca3(PO4)2(MW=Molecular Weight: 310.2 g/mol)

mol solute :

[tex]\tt \dfrac{15.9}{310.2}=0.0512[/tex]

The molality :

[tex]\tt \dfrac{0.0512}{0.4~kg}=0.128~m[/tex]

Answer:

Coefficients represents no of moles while subscripts represent no of atoms.

Answer:

Coefficients came before formula . Example = 4CO means there are 4 molecules of carbonmonooxide.

Subscripts came after and below the formula . Example = Oxygen gas in which 2 is a subscript which means there are 2 atoms of Oxygen in 1 molecule of Oxygen i.e. oxygen gas

Answer:

BIPHASIC LIQUIDS are used ear cleaning, to softening the wax so that mild infections can be treated.

Explanation:

BIPHASIC LIQUIDS are liquids that contain two immiscible phases, one is suspension and the other is emulsion. In suspension, the finely solid are dispersed in a liquid or semi solidwhich is use for medicament

The emulsion consist of immiscible liquids, one is dispersed in globules.

They are used ear cleaning, to softening the wax so that mild infections can be treated.

Hi

i hope this helps

Answer:

The Greek atom theory

Explanation:

The concept of the Greek atomos theory is an indivisible particle of matter, goes back to ancient Greece and a man named Democritus held that all matter could be subdivided only until some finite particle was reached.

Answer:

x = w/v

General Formulas and Concepts:

Pre-Algebra

Explanation:

Step 1: Define

v = w/x

Step 2: Solve for x

Answer:

-189.55°C

Explanation:

Given data:

Initial volume of gas = 3.6 L

Final volume of gas = 15.5 L

Initial temperature = ?

Final temperature = 87°C (87+273 = 360 K)

Solution:

The given problem will be solve through the Charles Law.

According to this law, The volume of given amount of a gas is directly proportional to its temperature at constant number of moles and pressure.

Mathematical expression:

V₁/T₁ = V₂/T₂

V₁ = Initial volume

T₁ = Initial temperature

V₂ = Final volume  

T₂ = Final temperature

Now we will put the values in formula.

V₁/T₁ = V₂/T₂

T₁  = V₁T₂  /V₂

T₁   = 3.6 L × 360 K / 15.5 L

T₁   = 1296 L.K / 15.5 L

T₁  = 83.6 K

Kelvin to °C:

83.6 K - 273.15 = -189.55°C

Answer:

B

Explanation:

The second one is not balanced correctly.

2 NaOH + 2HNO3 → 2NaNO3 + 2 H20

I didn't notice this before but it can be balanced without the twos.

 NaOH + HNO3 → NaNO3 +  H20

It was still wrong. It needed to have the twos removed, not 2 more added. Adding two more isn't wrong, but it should be balanced without 2s if at all possible.

Answer:

hexane C6H14

IS YOUR ANSWER

Explanation:

I HOPE IT HELPS MATE

MARK ME BRAINLIEST PLS

I WILL ALWAYS HELP YOU UNDERSTANDING YOUR ASSINGMENTS

HAVE A GREAT DAY

#CAPTAINPOWER :)

Explanation:

Kendrick gave the bat potential Energy

Answer:

E

because it forms the ionic bond but not covalent.

Answer:

the answer is b

Explanation:

brcause the gravutational pull on the moon is lower than on earth...

Answer:

Water from melting snow or rainfall infiltrates into cracks in rocks. ... As this process of freezing and thawing happens repeatedly, the rock begins to weaken and eventually breaks apart into angular fragments.

Explanation:

Water melting from snow or rainfall which infiltrates into cracks in rocks,  this is repeated process of freezing and thawing,  the rock begins to weaken and eventually breaks apart into angular fragments.

A rock can be formed due to the aggregation of mineral constituents in the earth’s crust and  it can be classified is based on different factors like Geological classification, Physical classification, Chemical classification.

Geological classification can be either Sedimentary rock formed by the deposition of sediments by the weathering of pre-existing rocks and it can be carried out by various agents like water, wind, gravity, etc.

Igneous rocks formed  by the  solidification of magma below the earth’s surface which is held together below the earth’s surface and unable to descend, when these magma cools down  and solidifies into igneous rocks.

Learn more about rock layer, here:

brainly.com/question/21634781

#SPJ6

There are 1.204 x 10¹⁹ atoms O

The empirical formula is the smallest comparison of atoms of compound forming elements.  

A molecular formula is a formula that shows the number of atomic elements that make up a compound.  

1 mol of molecule Na₂C₂O₄ :

There are 4 mol of O in 1 mol of molecule Na₂C₂O₄

So for 5 x 10⁻⁶ mol Na₂C₂O₄ :

[tex]\tt mol~O=4\times 5.10^{-6}=2.10^{-5}[/tex]

1 mole = 6.02.10²³ particles , so number of atoms O :

[tex]\tt 2\times 10^{-5}\times 6.02\times 10^{23}=1.204\times 10^{19}[/tex]

Answer:

The phosphorus ylide reacts with the aldehyde or ketone to make an oxaphosphetane.

Explanation:

The Wittig reaction is a reaction that occurs between a phosphorus ylide and an aldehyde or ketone. The final products are an alkene and triphenyl phosphine oxide.

The first step in the reaction is the attack of the phosphorus ylide on the aldehyde or ketone. This is followed by attack of oxygen on phosphorus to form a [2+2] cycloaddition product (oxaphosphetane)  which  decomposes to form the alkene and triphenylphosphine oxide.

Answer:

A

Explanation:

I took a test like this and my teacher said this was right so ye. hopefully I remembered correctly if its wrong im sorry ;C

Answer: A

Explanation: A thunderstorm forms when warm, moist air rises into cold air. Hope this helps. :)

Answer:

1. 0.28M

2. 24mL

3. 0.002295moles of NaOH.

Explanation:

1. The 6.0M HCl solution is diluted from 35mL to 750mL, that is:

750mL / 35mL = 21.43 times

The 6.0M HCl solution is diluted 21.43 times, the final concentration is:

6.0M / 21.43 = 0.28M

2. First, we need to convert grams of CuNO3 to moles and then, as molarity is moles per liter we can solve for volume of solution in liters and convert it to mililiters:

Moles CuNO3 -Molar mass 124.9g/mol:

2.49g * (1mol / 124.9g) = 0.020 moles of CuNO3

Volume is:

0.020 moles * (1L / 0.830mol) = 0.0240L * (1000mL / 1L) = 24mL

3. In 13.5mL = 0.0135L of 0.17M NaOH the moles are:

0.0135L * (0.17mol / L) = 0.002295moles of NaOH

it is push i think to move the car

Answer:

Either A. Push or B.Pull because the truck is either pushing or pulling the car to move it. So it depends on if it's pushing or pulling the car.

Explanation:

Answer:

help you with what?

Explanation:

Answer:

Explanation:

b

Answer:

20.39 g of O2.

Explanation:

We'll begin by writing the balanced equation for the reaction. This is illustrated below:

2KClO3 —> 2KCl + 3O2

Next, we shall determine the mass of KClO3 that decomposed and the mass of O2 produced from the balanced equation. This is illustrated below:

Molar mass of KClO3 = 122.4 g/mol

Mass of KClO3 from the balanced equation = 2 × 122.4 = 244.8 g

Molar mass of O2 = 32 g/mol

Mass of O2 from the balanced equation = 3 × 32 = 96 g

Summary:

From the balanced equation above,

244.8 g of KClO3 decomposed to produce 96 g of O2.

Finally, we shall determine the mass of O2 produced from the decomposition of 52 g of KClO3. This can be obtained as follow:

From the balanced equation above,

244.8 g of KClO3 decomposed to produce 96 g of O2.

Therefore, 52 g of KClO3 will decompose to produce =

(52 × 96)/244.8 = 20.39 g of O2.

Thus, 20.39 g of O2 is produced.

The equation is balanced. There are 4 aluminium atoms and 6 oxygen atoms on each side.

Answer: Since k2 corresponds to 64 hours, the time for the milk to sour at 40 C is 64 h / 9.38 = 6.8 hours.

Explanation:

At temperature T1, the Arrhenius Equation is:

k1 = Ae^(-Ea/RT1).

An equivalent equation can be written at T2:

k2 = Ae^(-Ea/RT2).

If these equations are divided, then A cancels:

k1/k2 = e^(-Ea/RT1)/e^(-Ea/RT2)

Taking the natural log:

ln(k1/k2) = (Ea/RT2)-(Ea/RT1);

or:

ln(k1/k2) = (Ea/R)(1/T2 - 1/T1)

We can infer from the question that the milk sours 3 times as fast at the higher temperature (let's call it T1), so we can arbitrarily call k2 = 1 and k1 = 3.

a) Substitute:

ln(3) =  (Ea/R)(1/276.15 K - 1/293.15 K).

We get Ea/R = 5231.6. Multiply this by whatever value of R you choose to get Ea in your favorite energy unit. Remember the sig figs.

b) Again, let's let the lower temperature = T2, since we have defined k2 = 1:

ln(k1) = (5231.6)(1/276.15 K - 1/313.15);

ln(k1) = 2.24, so k1 = 9.38.

Since k2 corresponds to 64 hours, the time for the milk to sour at 40 C is 64 h / 9.38 = 6.8 hours.

Answer:

1+2=2+1 is the answer for the question

Answer:

Electromagnets are widely used as components of other electrical devices, such as motors, generators, electromechanical solenoids, relays, loudspeakers, hard disks, MRI machines, scientific instruments, and magnetic separation equipment.

Explanation:

Hope this helps :)

(didn't get this from the internet)

Answer:

NaF, CaBr2, MgO

Explanation:

Hi! For this problem, you are going to want to look at the charges of the elements in order to write their formulas.

NaF: Na has a charge of +1 and F has a charge of -1. This means that they have a 1:1 ratio and the formula is written as such - NaF.

CaBr2: Ca has a charge of +2 and Br has a charge of -1. For this problem you want to make sure that their formal charge (the charge of the entire molecule) equals 0. This means that the negative charges need to equal the positive charges. Looking at this, you are going to need to Br ions with a charge of -1 to equal one Ca ion with a charge of +2 - CaBr2.

MgO: Mg has a charge of +2 and O has a charge of -2. This means that they have a 2:2 ratio which simplifies to a 1:1 ratio and the formula is written as such - MgO.

Hope this helps!

It's answer is c. N2

The maximum bond energy is of N2 because N2 molecule is formed by 3 covalent bonds and O2 molecule is formed by 2 covalent bonds.

Hope it helps :)

Answer: 2

Explanation:

A combustion reaction must include O2 as a reactant.

An inorganic substance almost never includes carbon.

So, by process of elimination:

1. Carbon is a reactant = probably not

2. Has O2, no carbon = yes

3. O2 is not a reactant = no

4. Carbon is a reactant = probably not

An example of the combustion of an inorganic substance is:

2 Ca + O₂ ⇒ 2 CaO

We have 4 reactions and we want to determine which is an example of combustion of an inorganic substance.

A combustion reaction is a reaction in which a substance reacts with oxygen gas, releasing energy in the form of light and heat.

Organic substances always contain carbon while most inorganic substances do not contain carbon.

Let's consider the following reactions.

This is a combustion reaction but C₃H₈ is an organic substance.

This is an example of the combustion of an inorganic substance.

This is not a combustion reaction.

This is a combustion reaction but CH₃COOH is an organic substance.

An example of the combustion of an inorganic substance is:

2 Ca + O₂ ⇒ 2 CaO

Learn more about combustion here: https://brainly.com/question/4155165

Answer:

Other possible quantum numbers would be.

A). When n = 3,

I = 0,

m1 = 0

ms = +1/2 or -1/2

B). When I = 1,

m1 = -1 or +1

ms = +1/2 or -1/2

C). When I = 2

m1 = -2,-1,0,1 or 2

ms = +1/2 or -1/2.

Answer:

Explanation:

proposed an early model of the atom as a central nucleus containing protons and neutrons being orbited by electrons in shells. As previously discussed, there is a connection between the number of protons in an element, the atomic number that distinguishes one element from another, and the number of electrons it has. In all electrically-neutral atoms, the number of electrons is the same as the number of protons. Each element, when electrically neutral, has a number of electrons equal to its atomic number.

Answer:

You can check diagram with number of proton neutron and electrons

Explanation:

Answer: (a) [tex]\Delta S^{0}[/tex] = - 242.2J/K.mol

              (b) [tex]\Delta S^{0}[/tex] = 163.34J/K.mol

              (c) Yes

Explanation: Entropy is the measure of randomness or disorder of a system. Standard Entropy has the symbol [tex]S^{0}[/tex].

Mathematically, Entropy is defined as

[tex]\Delta S^{0}=\Sigma S^{0}(products)-\Sigma S^{0}(reagents)[/tex]

Each substance has its own entropy value.

(a) Combustion of Methane:

[tex]CH_{4}+2O_{2}[/tex] ⇒ [tex]CO_{2}+2H_{2}O[/tex]

Using standard entropy table, entropy will be:

[tex]\Sigma S^{0}(products)=214+2(69.91)[/tex] = 353.8

[tex]\Sigma S^{0}=186.264+2(205.138)[/tex] = 596.54

[tex]\Delta S^{0}=[/tex] 353.8 - 596.54

[tex]\Delta S^{0}=[/tex] - 242.2

Standard Entropy for combustion of methane is [tex]\Delta S^{0}=[/tex] - 242.2 J/K.mol.

(b) Hydrolysis of Water:

[tex]H_{2}O_{(l)}[/tex] ⇒ [tex]H_{2}_{(g)}+1/2O_{2}_{(g)}[/tex]

[tex]\Sigma S^{0}(products)=130.684+0.5(205.138)[/tex] = 233.253

[tex]\Sigma S^{0}(reagents)=69.91[/tex]

[tex]\Delta S^{0}=[/tex] 233.253 - 69.91

[tex]\Delta S^{0}=[/tex] +163.34

Standard Entropy for hydrolysis of water is [tex]\Delta S^{0}=[/tex] + 163.34 J/K.mol

(c) Yes, the results prove the general rule: Reactions Entropies are positive for net formation of gas and negative for net reduction of gas. This happens because, as entropy is the measure of disorder, the entropy for gases are greater than for liquids and solids. So, when there is formation of a gas, Entropy increases and when there isn't, entropy decreases.