All categories

3 years ago

A compound of carbon and hydrogen contains 92.3 percent c and has a molar mass of 78.1g/mol. What is its molecular

Chemistry

1 answer:

alekssr [168]3 years ago

7 0

Answer:

C₆H₆

Explanation:

We need to find the molecular formula of a compound of carbon (C) and hydrogen (H), so what we need to find out is the number of atoms of C and of H in the molecule. We know:

molar mass = 78.1 g/mol
C% = 92.3% = 92.3 g C / 100 g compound

So, in 1 mol of compound, 92.3% of the mass corresponds to Carbon:

mass of C / mol of compound = molar mass × C% = 78.1 g/mol × 92.3/100 = 72.1 g/mol

moles of C = mass C / molar mass C = 72.1 g / 12.011 g/mol

moles of C = 6 moles of C per mol of compound

If 72.1 g in a mol of compound are Carbon atoms, the difference between the molar mass and the mass of Carbon atoms will correspond to H atoms in 1 mol of compound:

mass of H / mol of compound = molar mass - mass of C/mol

mass of H = 78.1 g / mol - 72.1 g /mol = 6.0 g/mol of compound

moles of H = mass H / molar mass H = 6.0 g / 1.008 g/mol

moles of H = 6.0 moles of H per mol of compound

So one mol of compound has 6 moles of C and 6 moles of H.

The molecular formula is then written as C₆H₆

You might be interested in

8. (02.04 MC)

elena55 [62]

Answer:

3p^2

Explanation:

after filling 3s^2 only two electrons left out of 14 so the next sub shell is 3p therefore ,X represents 3p^2

3 0

2 years ago

Which of the following is NOT true about the exothermic reaction?

Natasha2012 [34]

The statement that is not true about the exothermic reaction is that the potential energy of the product is higher than the potential energy of the reactant. That is option D.

<h3>What is an exothermic reaction?</h3>

An exothermic reaction is the reaction that releases heat to the environment which causes increase in the immediate environment.

The characteristics of exothermic reaction include the following:

Activation energy of the forward reaction is smaller than the activation energy of the reverse reaction.

Heat is released to the environment during reaction.

Since there is release of heat, the product will have a lower energy than the reactant.

Therefore, the statement that is not true about the exothermic reaction is that the potential energy of the product is higher than the potential energy of the reactant.

Learn more about exothermic reaction here:

brainly.com/question/2924714

#SPJ1

7 0

2 years ago

Mantle material rises in convection currents because heated materials becomes more dense

sergey [27]

Heated mater rises and cold mater sinks

3 0

3 years ago

A student experimentally determines the density of a metal cube. The edge length of the cube is measured using calipers. The cub

IgorC [24]

Answer:

10.9%.

Explanation:

The first thing to do in order to solve this question is to Determine the value for the volume of the the cube. This can be done by taking the cube root of the length of the cube;

The volume of the cube = (length of the cube)^3 = length × length × length = 1.72 × 1.72 × 1.72 =( 1.72)^3 = 5.09cm^3.

The next thing you do is to Determine the exponential density, the can be done by using the formula below;

The exponential density = mass/ volume = 55. 786/ 5.09 = 10.96 g/cm^3.

Therefore, the percent error = (true density of the cube - exponential density of the cube)÷ true density of the cube × 100.

Hence, the percent error = 12.30 - 10.96/12.30 × 100 = 10.9%.

8 0

3 years ago

I need to find the chemical equation

Yuri [45]

Answer:

2NaCN + CaCO3 --> Na2CO3 + Ca(CN)2

Explanation:

Knowing the names gets us: NaCN + CaCO3 --> Na2CO3 + Ca(CN)2

Balance: there are two sodiums and cyanides on the product side so add a 2 to the reactant side.

4 0

3 years ago