Determine the molar mass of CaO

Calculation: If a compound is 14.40% hydrogen by mass and 85.60% carbon by mass, what is the empirical formula?

IgorLugansk [536]

Answer:

CH2

Explanation:

We are given that a compound is 14.40% hydrogen and 85.60% carbon.

Let the mass of the substance be 100g.

Mass of the hydrogen: 14.40% of 100 = 14.40 g

Mass of the carbon: 85.60% of 100 = 85.60 g

Now, let's find the moles of hydrogen:

$14.40 g*\frac{1 mole}{1gH} = 14.40 mole$

Moles of carbon:

$85.60g*\frac{1 mol}{12gC} = 7.13mol$

Let's put these in a ratio and simplify:

7.13 mole C: 14.40 mole H

1 mole C: 2 mole H

Therefore, the empirical formula of this compound is CH2.

Hope this helps!! If you have any questions about my work, please let me know in the comments!

3 0

2 years ago

An atom of an element is shown by the model. How is the model useful

Orlov [11]

Answer:

I believe it is useful as it shows how electrons are distributed in the shells (energy levels) of an iron atom. An atom is the smallest particle of an element that can take part in a chemical reaction. It contains the nucleus and the shells (energy levels). the nucleus contains protons and neutrons while the shells contain electrons.

Explanation:

6 0

2 years ago

Compound Y has a distribution coefficient of 4.0 when extracted from water with chloroform, with Y being more soluble in chlorof

Aleks04 [339]

Answer:

There are needed 3 extractions to extract at least 95%

Explanation:

The distribution coefficient of a compound is defined as the ratio in concentration of the compound in the organic solvent and the concentration in the aqueous solution:

K = Concentration organic solvent / Concentration in water

Assuming as initial amount of the organic solvent: 100% and X as the amount of Y that is extracted

First extraction:

4 = X / 10mL / (100-X) / 50mL

4 = 50X / 1000-X

4000 - 4X = 50X

4000 = 54X

X = 74.1%

In the first extraction, 74.1% of Y is extracted

And will remain: 100 - 74.1 = 25.9%

Second extraction:

4 = X / 10mL / (25.9-X) / 50mL

4 = 50X / 259-X

1036 - 4X = 50X

1036 = 54X

X = 19.2%

In the second extraction, 19.2% of Y is extracted

And will remain: 25.9 - 19.2 = 6.7%

Third extraction

4 = X / 10mL / (6.7-X) / 50mL

4 = 50X / 67-X

268 - 4X = 50X

268 = 54X

X = 5.0%

In the first extraction, 5.0% of Y is extracted

And are extracted:

74.1% + 19.2% + 5.0% = 98.3%

That means there are needed 3 extractions to extract at least 95%

4 0

2 years ago

Write a balanced chemical equation for the standard formation reaction of gaseous formaldehyde CH2O

Free_Kalibri [48]

From the combustion of octane, the formaldehyde will be formed as this equation:

C8H18 + O2 → CH2O + H2O this is the original equation but it is not a balanced equation, so let's start to balance it:

the equation to be balanced so the number of atoms on the right side of the equation sholud be equal with the number of atoms on the lef side.

-we have 8 C atoms on left side and 1 atom on the right side so we will try putting 8 CH2O on the right side instead of CH2O

C8H18 + O2 → 8 CH2O + H2O

we have 2 O atoms on the left side and 9 atoms on the right side so we will try first to put 9 O2 instead of O2 on the left side and put 2H2O on the right side and put 16 CH2O instead of 8 CH2O to make the atoms of O are equal on both sides = 18 atoms

C8H18 + 9 O2 → 16 CH2O + 2H2O

put now we have 8 atom C on the left side and 16 atom on the right side so, we will put 2 C8H18 instead of C8H18 now we get this equation:

2C8H18 + 9O2 →16 CH2O + 2H2O

-now we have 36 of H atoms on both sides.

- and 16 of C atoms on both sides.

- and 18 of O atoms on both sides.

now all the number of atoms of O & C & H are equal on both sides

∴ 2C8H18 + 9O2 → 16 CH2O + 2 H2O

is the final balanced equation for the formation of formaldehayde

5 0

3 years ago

at atmoshperic pressure, a balloon contains 2.00L of nitrogen of gas. How would the volume change if the Kelvin temperature were

Nataly [62]

Answer: The percent change in volume will be 25 %

Explanation:

To calculate the final temperature of the system, we use the equation given by Charles' Law. This law states that volume of the gas is directly proportional to the temperature of the gas at constant pressure.

Mathematically,

$\frac{V_1}{T_1}=\frac{V_2}{T_2}$