Elements and Metals Science MCQS 1 TO 20

        Elements and Metals Science MCQS 1 TO 20

1.	Brass gets discoloured in air because of the presence of which of the following gases in air?
	A. Oxygen B. Hydrogen sulphide C. Carbon dioxide D. Nitrogen Answer & Explanation Answer: Option B

---

2.	Which of the following is a non metal that remains liquid at room temperature?
	A. Phosphorous B. Bromine C. Chlorine D. Helium Answer & Explanation Answer: Option B

---

3.	Chlorophyll is a naturally occurring chelate compound in which central metal is
	A. copper B. magnesium C. iron D. calcium Answer & Explanation Answer: Option B

---

4.	Which of the following is used in pencils?
	A. Graphite B. Silicon C. Charcoal D. Phosphorous Answer & Explanation Answer: Option A

---

5.	Which of the following metals forms an amalgam with other metals?
	A. Tin B. Mercury C. Lead D. Zinc Answer & Explanation Answer: Option B

6.	Chemical formula for water is
	A. NaAlO2 B. H2O C. Al2O3 D. CaSiO3 Answer & Explanation Answer: Option B

7.	The gas usually filled in the electric bulb is
	A. nitrogen B. hydrogen C. carbon dioxide D. oxygen Answer & Explanation Answer: Option A

---

8.

Washing soda is the common name for

A. Sodium carbonate B. Calcium bicarbonate C. Sodium bicarbonate D. Calcium carbonate Answer & Explanation 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.

---

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 & Explanation Answer: Option A

---

10.	Which of the gas is not known as green house gas?
	A. Methane B. Nitrous oxide C. Carbon dioxide D. Hydrogen Answer & Explanation 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

11.	Bromine is a
	A. black solid B. red liquid C. colourless gas D. highly inflammable gas Answer & Explanation Answer: Option B

---

12.	The hardest substance available on earth is
	A. Gold B. Iron C. Diamond D. Platinum Answer & Explanation Answer: Option C

---

13.	The variety of coal in which the deposit contains recognisable traces of the original plant material is
	A. bitumen B. anthracite C. lignite D. peat Answer & Explanation Answer: Option D

---

14.	Tetraethyl lead is used as
	A. pain killer B. fire extinguisher C. mosquito repellent D. petrol additive Answer & Explanation Answer: Option D

---

15.	Which of the following is used as a lubricant?
	A. Graphite B. Silica C. Iron Oxide D. Diamond Answer & Explanation Answer: Option A

16.	The inert gas which is substituted for nitrogen in the air used by deep sea divers for breathing, is
	A. Argon B. Xenon C. Helium D. Krypton Answer & Explanation Answer: Option C

---

17.	The gases used in different types of welding would include
	A. oxygen and hydrogen B. oxygen, hydrogen, acetylene and nitrogen C. oxygen, acetylene and argon D. oxygen and acetylene Answer & Explanation Answer: Option D

---

18.	The property of a substance to absorb moisture from the air on exposure is called
	A. osmosis B. deliquescence C. efflorescence D. desiccation Answer & Explanation Answer: Option B

---

19.	In which of the following activities silicon carbide is used?
	A. Making cement and glass B. Disinfecting water of ponds C. cutting very hard substances D. Making casts for statues Answer & Explanation Answer: Option C

---

20.	The average salinity of sea water is
	A. 3% B. 3.5% C. 2.5% D. 2% Answer & Explanation Answer: Option B

Please Give Us Your 1 Minute In Sharing This Post!

SOCIALIZE IT →

Tweet

FOLLOW US →

SHARE IT →

Powered By: Latestmcqs.com