Learn more about the properties, composition, and structure of substances (elements and compounds) with these Chemistry questions and answers. This Test can be used by students preparing for Chemistry in JAMB, WAEC, NECO or Post UTME.
The cleansing effect of soap is low in acidic water because of
the formation of unionized fatty acid.
increase in the pH of the soap molecules.
anti-biodegradable effect of hydrogen ions
the hardness of the acidic water.
Correct answer is A
Soaps cannot be used in acidic condition because they lose their cleansing effect due to the formation of long chain fatty acids
Which of the following sugars is a product of the condensation of monosaccharides?
galactose
maltose
glucose
fructose
Correct answer is B
Maltose is produced by the enzymatic hydrolysis of starch (a homopolysaccharide) catalyzed by the enzyme amylase.
The by-product of fermentation of sugar is
carbon(IV) oxide.
ethanoic acid.
propanol
propan-1, 2, 3- triol.
Correct answer is A
Ethanol fermentation, also called alcoholic fermentation, is a biological process which converts sugars such as glucose, fructose, and sucrose into cellular energy, producing ethanol and carbon dioxide as by-products
| GAS | CO\(_2\) | N\(_2\) |
O\(_2\) |
| % BY VOLUME | 4 | 72 | 24 |
The above table shows the compositions of the atmosphere of planet X. Which of these gases are present in higher percentages on earth?
CO\(_2\) and O\(_2\)
N\(_2\) and CO\(_2\)
CO\(_2\), O\(_2\) and N\(_2\)
O\(_2\) and N\(_2\)
Correct answer is D
The air in Earth's atmosphere is made up of approximately 78 percent nitrogen and 21 percent oxygen. Air also has small amounts of other gases, too, such as carbon dioxide, neon, and hydrogen.
30
40
20
50
Correct answer is B
To make a fixed amount of a dilute solution from a stock solution,
use the formula: C1V1 = C2V2
where: V1 = Volume of stock solution needed to make the new solution.
C1 = Concentration of stock solution.
V2 = Final volume of new solution.
C2 = Final concentration of stock solution
2 * 10 = 0.5 * V2
20 = 0.5V2
\(\frac{20}{0.5}\) = V2
= 40dm\(^3\)