1271. What is the only element that normally has no neutrons ?
A. Oxygen
B. Hydrogen *
C. Krypton
D. Neon
1272. Which of these is not a noble gas?
A. Argon
B. Hydrogen *
C. Krypton
D. Neon
1273. What is the primary component of natural gas and biogas?
A. Ethane
B. Butane
C. Propane
D. Methane *
1274. Which one of the following is the softest ?
A. Iron *
B. Lithium
C. Iron
D. Sodium
1275. Which of the following elements shares the same atomic weight and number?
A. Hydrogen *
B. Helium
C. Oxygen
D. Nitrogen
1276. All organic compounds contain which of the following elements?
A. Calcium
B. Carbon *
C. Nitrogen
D. Oxygen
1277. The purest form of iron is :
A. Pig iron
B. Cast iron
C. Wrought iron *
D. Stainless steel
1278. The most malleable metal is :
A. Platinum
B. Silver
C. Iron
D. Gold *
1279. The major consituent of air is :
A. Nitrogen *
B. Carbon Dioxide
C. Oxygen
D. Hydrogen
1280. The first metal to be used by man was :
A. Aluminium
B. Copper *
C. Silver
D. Iron