Elements And Metals : 1

Question 6 :

Chemical formula for water is

A). NaAlO2
B). H2O
C). Al2O3
D). CaSiO3
Answer : Option B

Question 7 :

The gas usually filled in the electric bulb is

A). nitrogen
B). hydrogen
C). carbon dioxide
D). oxygen
Answer : Option A

Question 8 :

Washing soda is the common name for

A). Sodium carbonate
B). Calcium bicarbonate
C). Sodium bicarbonate
D). Calcium carbonate
Answer : Option A

Explanation :

What is the scientific name for washing soda?
Sodium carbonate (also known as washing soda or soda ash), Na2CO3 is a sodium salt of carbonic acid.
Scientific name for baking soda?
Sodium bicarbonate or sodium hydrogen carbonate is the chemical compound with the formula NaHCO3. Sodium bicarbonate is a white solid that is crystalline but often appears as a fine powder. Since it has long been known and is widely used, the salt has many related names such as baking soda, bread soda, cooking soda, and bicarbonate of soda.

Question 9 :

Quartz crystals normally used in quartz clocks etc. is chemically

A). silicon dioxide
B). germanium oxide
C). a mixture of germanium oxide and silicon dioxide
D). sodium silicate
Answer : Option A

Question 10 :

Which of the gas is not known as green house gas?

A). Methane
B). Nitrous oxide
C). Carbon dioxide
D). Hydrogen
Answer : Option D

Explanation :

In order, the most abundant greenhouse gases in Earth's atmosphere are:
* water vapor
* carbon dioxide
* methane
* nitrous oxide
* ozone
* chlorofluorocarbons