A42.0g sample of compound containing only c and h was analyzed. the results showed that the sample contained 36.0g of c and 6.0g of h. which of the following questions about the compound can be answered using the results of the analysis?

Molar mass of C_3H_6 = 36 g mol^-1 +6g mol^-1 =42g mol^-1

Empirical formula of Sample = (CH_3)

Explanation:

Mass sample having only C and H = 42g

Mass of C = 12g mol^-1

Molar mass of C = 12g mol^-1

Moles of C = 36 g / 12g mol^-1

= 3 mol

Mass of H in sample = 6g

Molar mass of H = 1 g mol^-1

Moles of H = 6g / 1g mol^-1

= 6 mol

Therefore in 42g sample 3 mol of C + 6 mol of H present, that is C_3H_6

Molar mass of C_3H_6 = 36 g mol^-1 +6g mol^-1 =42g mol^-1

Empirical formula of Sample = (CH_3)

We can solve the question 'What is the empirical formula of the compound?' The answer is CH2

Explanation:

A 42.0g sample of compound containing only C and H was analyzed. The results showed that the sample contained 36.0g of C and 6.0g of H. Which of the following questions about the compound can be answered using the results of the analysis?

A) What was the volume of the sample?

B) What is the molar mass of the compound?

C) What is the chemical stability of the compound?

D) What is the empirical formula of the compound?

Step 1: Data given

Mass of the compound = 42.0 grams

⇒ 36.0 grams = carbon

⇒ 6.0 grams = hydrogen

Molar mass of carbon = 12.01 g/mol

Molar mass of hydrogen = 1.01 g/mol

Step 2: Calculate moles

Moles = mass / molar mass

Moles Carbon = 36.0 grams / 12.01 g/mol

Moles carbon = 3.00 moles

Moles hydrogen = 6.0 grams / 1.01 g/mol

Moles hydrogen = 5.95 moles

Step 3: Calculate mol ratio

We divide by the smallest number of moles

Carbon: 3.00 / 3.00 = 1

Hydrogen: 5.95 / 3.00 = 2

The empirical formula is CH2

a mercury barometer is a device that uses the physical properties of mercury in a tube to measure barometric pressure. mercury barometers are used for : -

1. measurement of atmospheric pressure  

2. determining the altitude of a place

3. weather forecasting

4. calibration and checking of aneroid barometers

5. application in fluid mechanics

6. measurement of pressure in aircrafts

7. surface weather analysis

8. preparation of barographs

9. usage in physical sciences like physics, astronomy & chemistry

10. preparation of aircraft altimeters

characteristics of mercury barometer : -

1.used to define and measure atmospheric pressure.

2.on the average at sea level the column of mercury rises to a height of about 760 mm.

3.this quantity is equal to 1 atmosphere.

4.it is also known as standard atmospheric pressure.

5.a barometer in which the weight of a column of mercury in a glass tube with a sealed top is balanced against that of the atmosphere pressing on an exposed cistern of mercury at the base of the mercury column, the height of the column varying with atmospheric pressure.