2.24 dm3
4.48dm3
22.4dm3
44.8dm 3
Correct answer is B
2g of H\(_2\) = 22.4 dm\(^3\)
0.4g of H\(_2\) = x,
x = \(\frac{0.4 \times 22.4}{2}\) = 4.48dm\(^3\)
Which of the following metals would readily displace hydrogen from steam?
Copper
Lead
Magnesium
Silver
Correct answer is C
In the electrochemical series, H\(^+\) is above all the other elements in the series except Magnesium. Hence, only Mg\(^{2+}\) can displace hydrogen from a reaction.
conservation of mass
definite proportion
multiple proportion
reciprocal proportion
Correct answer is C
Law of multiple proportions, statement that when two elements combine with each other to form more than one compound, the weights of one element that combine with a fixed weight of the other are in a ratio of small whole numbers.
A sample of a gas may be identified as chlorine if it turns
damp blue litmus paper red
lime water miky
lead ethanoate paper black
starch iodide paper blue-black
Correct answer is D
A test for chlorine is to place damp starch-iodide paper into a test tube of chlorine. A positive result for chlorine is indicated by the paper turning from white to blue-black.
The formula of mercury (l) dioxonitrate (III) is
HgNO3
Hg2NO2
Hg2(NO2)2
Hg(NO3)2
Correct answer is C
No explanation has been provided for this answer.