Chemistry 5.1

Question 1

Equation for molar gas volume

Answer 1

moles = volume (dm3) / 24
volume (dm3) = moles x 24

Question 2

Equation for concentration of a solution

Answer 2

concentration = moles of solute/volume of solvent (dm3)

Question 3

How would you convert 5cm3 into dm3

Answer 3

5 / 1000 = 0.005 dm3

Question 4

Define concordant results

Answer 4

Results that differ from each other by 0.2cm3 or less

Question 5

What is a volumetric pipette used to measure?

Answer 5

Measures out 25cm3 very accurately (doesn’t measure any other volume)

Question 6

What is a burette used to measure?

Answer 6

Measures any volume to the nearest 0.05cm3

Question 7

Why is titration performed on top of a white tile?

Answer 7

To see the colour change at the end point clearly

Question 8

Steps to take during titration to obtain an accurate result

Answer 8

Repeat the method with clean conical flask
Add dropwise to more accurately reach the end point
Swirl the conical flask throughout
Repeat until concordant results are obtained and then calculate average.

Question 9

Convert 5dm3 into cm3

Answer 9

5 x 1000 = 5000 cm3

Question 10

Units for concentration

Answer 10

mol/dm3

Question 11

What is titration used for?

Answer 11

To measure the volume of titre of acid needed to neutralise a particular volume of alkali or vice-versa.