Specific Gravity

Question 1

Use of specific gravity

Answer 1

Solve for a liquid’s volume when the weight of the liquid is known

Question 2

Unit of the specific gravity

Answer 2

No unit

Question 3

Formula for getting the volume

Answer 3

Mass of the oil
——————— = volume to be taken
Specific gravity

Question 4

Define specific gravity

Answer 4

The ratio of the weight of a substance to the weight of an equal volume of water at 25C

Question 5

If 10 mL of sulfuric acid weigh 18 g, and 10 mL of water
under similar conditions, weigh 10 g, what is the specific
gravity of sulfuric acid is?

Answer 5

Weight of 10 ml of sulfuric acid 18(g)
——————————————— = ———— = 1.8
Weight of 10ml of water 10(g)

Question 6

Why is water used in finding the specific gravity?

Answer 6

Water has the density of 1g/cm³
Water has equal mass and volume

Question 7

What is the condition for density and specific gravity to be numerically equal?

Answer 7

All the units used should be in the metric system

Question 8

Formula of specific gravity

Answer 8

Weight of a certain volume of a substance
Specific gravity = ————————————————————
Weight of the same volume of water

Question 9

State the differences between specific gravity and density

Answer 9

1. Density has a unit, specific gravity don’t.
2. Specific gravity is constant for each substance, density is not constant

Question 10

If 54.96 mL of oil weigh 52.78 g, what is its density
and its specific gravity of this oil?

Answer 10

0.9603 g/mL and 0.9603 respectively

Question 11

What is specific gravity of 10 mL of mineral oil
which weigh 8.5 grams?

Answer 11

0.85

Question 12

Name the apparatus used to calculate specific gravity

Answer 12

Pycnometer

Question 13

How to use the pyctometer?

Answer 13

1. Weight the empty bottle
2. Fill it with water
3. Calculate the mass of water
4. Remove the water and fill the bottle with the liquid
5. Calculate the mass of the liquid
6. Mass of the substance / mass of the water for the same volume of the liquid

Question 14

Define specific volume

Answer 14

The volume occupied by 1g of a substance at a given temperature and pressure

Question 15

Formula of specific volume

Answer 15

1/density
(Reciprocal of the density)

Question 16

Specific gravity of urine in normal adults

Answer 16

1.01 to 1.025

Question 17

High specific gravity of urine indicates that:

Answer 17

1. Urine is concentrated
2. Presence of excess electrolytes (salts)
3. Presence of glucose or protein
4. Excess water loss
5. Decreased fluid intake

Question 18

Low specific gravity of urine indicates that:

Answer 18

1. Urine is dilute
2. May result in diabetes or renal disease
3. Increased fluid intake
4. Intravenous hydration

Question 19

Specific gravity in modern laboratories is determined by:

Answer 19

Refractive index