# Objective Chemistry Question.(1)

1) SI unit of time is

1. Second
2. Minute
3. Hour
4. Day

Explanation:

## Seven SI Base Units

Physicall Quantity Unit NameUnit Symbol
LengthMeterm
MassKilogramkg
TimeSeconds(sec)
Electric CurrentAmpereA(amp.)
TemperatureKelvinK
Ligh IntensityCandelacd
AmountMolemol

2) SI unit of mass is

1. Gram
2. Kilogram
3. Pound
4. None

Explanation:

## Seven SI Base Units

Physicall Quantity Unit NameUnit Symbol
LengthMeterm
MassKilogramkg
TimeSeconds(sec)
Electric CurrentAmpereA(amp.)
TemperatureKelvinK
Ligh IntensityCandelacd
AmountMolemol

3) SI unit of length is

1. Angstrom
2. Millimeter
3. Metre
4. Kilometre

Explanation:

## Seven SI Base Units

Physicall Quantity Unit NameUnit Symbol
LengthMeterm
MassKilogramkg
TimeSeconds(sec)
Electric CurrentAmpereA(amp.)
TemperatureKelvinK
Ligh IntensityCandelacd
AmountMolemol

4) SI unit of temperature is

2. Fahrenheit
3. Absolute
4. Kelvin

Explanation:

## Seven SI Base Units

Physicall Quantity Unit NameUnit Symbol
LengthMeterm
MassKilogramkg
TimeSeconds(sec)
Electric CurrentAmpereA(amp.)
TemperatureKelvinK
Ligh IntensityCandelacd
AmountMolemol

5) A microgram is written as

1. 103g
2. 106g
3. 10-6g
4. 10-3g

Explanation:

10-3g

6) Given the numbers : 161 cm, 0 . 161 cm, 0.0161 cm. The number of significant figures for the three numbers is

1. 3,4 and 5 respectively
2. 3,3 and 3 respectively
3. 3, 3 and 4 respectively
4. 3, 4 and 4 respectively

Explanation:

3,3 and 3 respectively.

7) Derive SI unit of area is

1. Cm2
2. Cm3
3. M2
4. M3

Explanation:

M2.

8) A substance which cant't be future decomposed by ordinary chemical means is

1. Water
2. Air
3. Sugar
4. Silver

Explanation:

Silver.

9) Which of following processes is a chemical change ?

1. Dissolution of common salt in water
2. Heating a platinum wire
3. Dissolution of sodium metal in water
4. Heating of water

Explanation:

Dissolution of sodium metal in water.

10) Which one is a physical change ?

1. Burning of S in air
2. Burning of S in air
3. Conversion of which phosphorus to red phosphorus
4. Corrosion of metals