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This section includes 255 Mcqs, each offering curated multiple-choice questions to sharpen your Science knowledge and support exam preparation. Choose a topic below to get started.
151. |
Mass of an element in a compound can be calculated through |
A. | Ar of the atoms/Mr of the compound |
B. | Mr of the atoms/Ar of the compound |
C. | (Ar of the atoms/Mr of the compound) × mass of sample |
D. | (Mr of the compound/Ar of the atoms) × mass of sample |
Answer» D. (Mr of the compound/Ar of the atoms) × mass of sample | |
152. |
Combining Copper(II) (Cu+2) with Oxygen (O₂) results in |
A. | CuO |
B. | Cu₂O |
C. | CuO₂ |
D. | Cu(OH)₂ |
Answer» B. Cu₂O | |
153. |
Valency of all these ions is negative 1, except |
A. | OH |
B. | PO₄ |
C. | NO₃ |
D. | Br |
Answer» C. NO₃ | |
154. |
In H₂SO₄, chemical composition of oxygen is |
A. | 0.1111 |
B. | 0.5032 |
C. | 0.6531 |
D. | 0.3265 |
Answer» D. 0.3265 | |
155. |
In Calcium Hydroxide (Ca(OH)₂), valency of Ca is |
A. | −1 |
B. | −2 |
C. | +1 |
D. | +2 |
Answer» E. | |
156. |
Metal that burns even more brightly than Magnesium (Mg) is |
A. | zinc |
B. | mercury |
C. | zirconium |
D. | diamond |
Answer» D. diamond | |
157. |
In writing chemical equations, inclusion of state symbols shall be done while |
A. | correct chemical formulae of reactants and products are written |
B. | the equation is being balanced to fulfill the law of conservation of mass |
C. | the equation has been balanced |
D. | the chemical formulae of products and reactants have been changed to bring about quick balancing |
Answer» D. the chemical formulae of products and reactants have been changed to bring about quick balancing | |
158. |
Sulfite ion can be written symbolically as |
A. | SO₄−2 |
B. | SO₃−2 |
C. | SO₄−3 |
D. | S−2 |
Answer» C. SO₄−3 | |
159. |
Natural gas consists of |
A. | methane |
B. | ethane |
C. | propane |
D. | butane |
Answer» B. ethane | |
160. |
Hydrogen Sulfate (H₂SO₄) has |
A. | positive charge |
B. | negative charge |
C. | double negative charge |
D. | double positive charge |
Answer» C. double negative charge | |
161. |
If an acid reacts with an oxide, product will include H₂O and |
A. | a salt(s) |
B. | an acid (l) |
C. | a base |
D. | a gas |
Answer» B. an acid (l) | |
162. |
The ratio of hydrogen to oxygen in a water molecule is equal to |
A. | 1:2 ratio |
B. | 2:1 ratio |
C. | 4:3 ratio |
D. | 1:4 ratio |
Answer» C. 4:3 ratio | |
163. |
The simple molecular structure is of |
A. | Na₂O |
B. | MgO |
C. | SiO₂ |
D. | P₄O₁₀ |
Answer» E. | |
164. |
The compounds which are made up of benzene are known as |
A. | aryl compounds only |
B. | aromatic compounds only |
C. | benzyl compounds |
D. | aryl and aromatic compounds |
Answer» E. | |
165. |
Formula K₂SO₄ indicates that |
A. | 2 ions of Kalium are combined with 4 molecules of oxygen |
B. | 2 ions of Kalium are combined with 1 sulfate ion |
C. | 2 ions of potassium are combined with one sulfur and 4 oxygen molecules |
D. | 1 ion of potassium is combined with 1 sulfate ion |
Answer» C. 2 ions of potassium are combined with one sulfur and 4 oxygen molecules | |
166. |
In Na₂CO₃.10H₂O, highest percentage composition is of |
A. | sodium |
B. | oxygen |
C. | water |
D. | carbon |
Answer» D. carbon | |
167. |
In acid and base reaction, product includes |
A. | a salt(s) |
B. | water |
C. | acids |
D. | both a and b |
Answer» D. both a and b | |
168. |
Chemical formula of Copper(I) Oxide |
A. | Cu₂O |
B. | CuO₃ |
C. | Cu(OH)₂ |
D. | CuO |
Answer» B. CuO₃ | |
169. |
The purification of compounds is usually done by chemists for formula analysis by the process of |
A. | gas chromatography |
B. | spectrometry |
C. | liquid chromatography |
D. | manometer |
Answer» B. spectrometry | |
170. |
Molar mass of calcium chloride is |
A. | 100.01gmol-1 |
B. | 99.98gmol-1 |
C. | 110.98gmol-1 |
D. | 88.2gmol-1 |
Answer» D. 88.2gmol-1 | |
171. |
Sulfuric acid is synthesized by the process of |
A. | Haber |
B. | contact |
C. | electrolysis |
D. | hydrolysis |
Answer» C. electrolysis | |
172. |
Formula of Calcium Hydrogen Carbonate indicates |
A. | that the charge on Ca is +2 |
B. | the charge on HCO₃ is −1 |
C. | that for each molecule of calcium hydrogen carbonate, one ion of Ca and two ions of hydrogen carbona |
D. | all of these |
Answer» E. | |
173. |
In Na₂CO₃.10H₂O, percentage of Carbon is |
A. | 0.4201 |
B. | 0.0422 |
C. | 0.042 |
D. | 0.46 |
Answer» D. 0.46 | |
174. |
In KHCO₃, highest percentage composition is of |
A. | Oxygen |
B. | Potassium |
C. | Carbon |
D. | Hydrogen |
Answer» B. Potassium | |
175. |
Ca(OH)₂ indicates that molecule is formed through |
A. | two Ca ions and one OH ion |
B. | One Ca ion and two OH ions |
C. | the charge on OH ion is -2 |
D. | the charge on OH ion is +2 |
Answer» C. the charge on OH ion is -2 | |
176. |
Empirical formula can be obtained if following is known: |
A. | %age or mass of each element |
B. | relative atomic mass Ar |
C. | structural formula |
D. | both a and b |
Answer» E. | |
177. |
Covalent compounds |
A. | are not made of ions |
B. | are not formed through exchange of electrons |
C. | formulae cannot be worked out |
D. | all of these |
Answer» E. | |
178. |
Magnesium (Mg) burns in oxygen (O₂) to form |
A. | magnesium peroxide (Mg₂O₂) |
B. | magnesium hydroxide (Mg(OH)₂) |
C. | magnesium oxide (MgO) |
D. | magnesium dioxide (MgO₂) |
Answer» D. magnesium dioxide (MgO₂) | |
179. |
In a benzene molecule, each carbon atom shares one pair of electrons to |
A. | neighboring atom on one side |
B. | neighboring atom on other side |
C. | hydrogen atom |
D. | all of above |
Answer» E. | |
180. |
In Sulfuric Acid (H₂SO₄), chemical composition of sulfur is |
A. | 0.0204 |
B. | 0.3265 |
C. | 0.6531 |
D. | 0.9821 |
Answer» C. 0.6531 | |
181. |
Organic molecules with similar relative molecular mass have alcohols (CₙH₂ₙ₊₁OH) bearing high |
A. | boiling point |
B. | polarity |
C. | volatility |
D. | Sublimation point |
Answer» B. polarity | |
182. |
When Carbon ions (C±4) react with Carbon Dioxide gas (CO₂), product will be |
A. | methane |
B. | ethane |
C. | propane |
D. | carbon monoxide |
Answer» E. | |
183. |
Consider CaCO₃ and HCl as reactants, how many molecules of CaCl₂ will be formed in products |
A. | 1 |
B. | 2 |
C. | 3 |
D. | 4 |
Answer» B. 2 | |
184. |
Valency of nitrogen can be |
A. | 2 or 4 |
B. | 4 or 6 |
C. | 3 or 5 |
D. | 2 or 3 |
Answer» D. 2 or 3 | |
185. |
Calcium carbonate CaCO₃ is a |
A. | solid |
B. | liquid |
C. | gas |
D. | aqueous |
Answer» B. liquid | |
186. |
π-bonds in benzene spread over all six carbons, hence they are called |
A. | delocalized |
B. | spectators |
C. | inhibitors |
D. | invaders |
Answer» B. spectators | |
187. |
Molar mass of potassium hydrogen carbonate KHCO₃ is |
A. | 90.15g/mol |
B. | 100.115g/mol |
C. | 111.127g/mol |
D. | 119.21g/mol |
Answer» C. 111.127g/mol | |
188. |
In Na₂CO₃, relative atomic mass of Carbon is |
A. | 12 |
B. | 24 |
C. | 36 |
D. | 48 |
Answer» B. 24 | |
189. |
Greatest proportion by mass of nitrogen is in |
A. | Hydrazine (N₂H₄), |
B. | ammonium nitrate (NH₄NO₃) |
C. | ammonium sulphate (NH₄)₂SO₄ |
D. | urea (NH₂CONH₂) |
Answer» B. ammonium nitrate (NH₄NO₃) | |
190. |
Chemical formula of monohydrate monosodium phosphate is |
A. | H₂ONaPO₂ |
B. | PO₂NaH₂O |
C. | NaH₂PO₄.H₂O |
D. | NaH₃PO₂.H₂O |
Answer» D. NaH₃PO₂.H₂O | |
191. |
Chemical formula of aluminum oxide is |
A. | Al₂O₃ |
B. | AlO₄ |
C. | Al₂O₅.H₂O |
D. | Al₂O₅ |
Answer» B. AlO₄ | |
192. |
Symbol of Gold has been derived from its Latin name |
A. | Argentum |
B. | Argon |
C. | Aurum |
D. | Augmenten |
Answer» D. Augmenten | |
193. |
Valency is numerically equal to |
A. | the charge of an ion |
B. | the combining power of an atom |
C. | the combining power of a radical |
D. | all of these |
Answer» E. | |
194. |
Chemical formula of calcium nitrate is |
A. | CNOH |
B. | Ca(NO₃)₂ |
C. | CaNO₃ |
D. | CaNO₃ |
Answer» C. CaNO₃ | |
195. |
In Na₂CO₃, relative atomic mass of Oxygen is |
A. | 12 |
B. | 24 |
C. | 36 |
D. | 48 |
Answer» E. | |
196. |
If atomic mass of copper is 63.546, mass percent of copper in Cu₂O will be |
A. | 0.7898 |
B. | 0.8098 |
C. | 0.8882 |
D. | 0.8678 |
Answer» D. 0.8678 | |
197. |
In Na₂CO₃.10H₂O, percentage of water is |
A. | 0.5009 |
B. | 0.1699 |
C. | 0.6507 |
D. | 0.6294 |
Answer» E. | |
198. |
A white smoke consisting of fine white solid particles is formed by |
A. | propane |
B. | butane |
C. | magnesium oxide |
D. | tin oxide |
Answer» D. tin oxide | |
199. |
All of these radicals have a valency of 1, except |
A. | OH |
B. | CO₃ |
C. | NO₃ |
D. | HCO₃ |
Answer» C. NO₃ | |
200. |
Formula of carbonic acid is |
A. | HCO₂ |
B. | HCHO₃ |
C. | H₂CO₂ |
D. | H₂CO₃ |
Answer» E. | |