MCAT / MDCAT Practice Test
Instructions: Select the correct option for each question.
B. Chemistry Section
101. The atomic number of an element represents:
A. Number of neutrons
B. Number of electrons and neutrons
C. Number of protons
D. Atomic mass
102. Which particle has no charge?
A. Proton
B. Electron
C. Neutron
D. Positron
103. The maximum number of electrons that can be accommodated in the second shell is:
A. 2
B. 8
C. 18
D. 32
104. Isotopes of an element differ in:
A. Number of protons
B. Number of electrons
C. Number of neutrons
D. Atomic number
105. The bond formed by sharing electrons is called:
A. Ionic bond
B. Metallic bond
C. Covalent bond
D. Hydrogen bond
106. Which of the following is an ionic compound?
A. H₂O
B. CO₂
C. NaCl
D. NH₃
107. Avogadro’s number is:
A. 6.02 × 10²²
B. 6.02 × 10²³
C. 3.01 × 10²³
D. 9.11 × 10³¹
108. The pH of a neutral solution is:
A. 0
B. 14
C. 7
D. 1
109. Which acid is present in gastric juice?
A. Sulfuric acid
B. Nitric acid
C. Hydrochloric acid
D. Acetic acid
110. The molecular formula of glucose is:
A. C₆H₁₂O₆
B. CH₄
C. C₂H₅OH
D. H₂SO₄
111. Which gas is evolved when acids react with metals?
A. Oxygen
B. Nitrogen
C. Hydrogen
D. Carbon dioxide
112. The SI unit of pressure is:
A. Joule
B. Pascal
C. Newton
D. Watt
113. Which law states that volume is inversely proportional to pressure?
A. Charles’ law
B. Boyle’s law
C. Gay-Lussac’s law
D. Avogadro’s law
114. Which element is present in all organic compounds?
A. Oxygen
B. Nitrogen
C. Carbon
D. Hydrogen
115. The process of loss of electrons is called:
A. Reduction
B. Oxidation
C. Neutralization
D. Hydrolysis
116. Which of the following is a strong acid?
A. Acetic acid
B. Carbonic acid
C. Hydrochloric acid
D. Formic acid
117. The shape of methane molecule is:
A. Linear
B. Trigonal planar
C. Tetrahedral
D. Bent
118. The empirical formula of benzene is:
A. CH
B. C₆H₆
C. CH₂
D. C₂H₂
119. Which of the following is an alkali metal?
A. Calcium
B. Sodium
C. Magnesium
D. Aluminum
120. The process of converting solid directly into gas is called:
A. Condensation
B. Sublimation
C. Evaporation
D. Freezing
121. The atomic mass unit is defined as:
A. Mass of one proton
B. 1/16th mass of oxygen atom
C. 1/12th mass of carbon-12 atom
D. Mass of one electron
122. Which orbital has a dumbbell shape?
A. s-orbital
B. p-orbital
C. d-orbital
D. f-orbital
123. The valency of oxygen is:
A. 1
B. 2
C. 3
D. 4
124. Which of the following has the highest electronegativity?
A. Fluorine
B. Chlorine
C. Oxygen
D. Nitrogen
125. The number of moles in 18 g of water is:
A. 0.5
B. 1
C. 2
D. 18
126. Which gas is known as laughing gas?
A. NO
B. NO₂
C. N₂O
D. NH₃
127. The catalyst used in the Haber process is:
A. Platinum
B. Iron
C. Nickel
D. Copper
128. Which of the following is a greenhouse gas?
A. Oxygen
B. Nitrogen
C. Carbon dioxide
D. Helium
129. Rusting of iron requires:
A. Water only
B. Oxygen only
C. Water and oxygen
D. Nitrogen and oxygen
130. Which of the following is an example of an exothermic reaction?
A. Photosynthesis
B. Respiration
C. Melting of ice
D. Evaporation
131. The formula of sulfuric acid is:
A. HCl
B. HNO₃
C. H₂SO₄
D. CH₃COOH
132. The gas collected over water should be:
A. Highly soluble in water
B. Insoluble in water
C. Reactive with water
D. Acidic
133. Which metal is liquid at room temperature?
A. Sodium
B. Mercury
C. Zinc
D. Iron
134. The pH of an acidic solution is:
A. Greater than 7
B. Equal to 7
C. Less than 7
D. Equal to 14
135. Which of the following is a noble gas?
A. Chlorine
B. Nitrogen
C. Neon
D. Hydrogen
136. The process of gaining electrons is called:
A. Oxidation
B. Reduction
C. Sublimation
D. Combustion
137. Which of the following is used in dry cells?
A. Sodium chloride
B. Ammonium chloride
C. Potassium nitrate
D. Calcium carbonate
138. The lightest element is:
A. Helium
B. Lithium
C. Hydrogen
D. Oxygen
139. Which vitamin contains cobalt?
A. Vitamin A
B. Vitamin B₁₂
C. Vitamin C
D. Vitamin D
140. The boiling point of water at standard pressure is:
A. 50°C
B. 75°C
C. 100°C
D. 120°C
141. Which of the following is an unsaturated hydrocarbon?
A. Methane
B. Ethane
C. Ethene
D. Propane
142. The formula of ammonia is:
A. NH₄
B. NH₃
C. NO₂
D. N₂O
143. Which acid is found in vinegar?
A. Sulfuric acid
B. Acetic acid
C. Hydrochloric acid
D. Nitric acid
144. The process of decomposition by electricity is called:
A. Electrolysis
B. Hydrolysis
C. Distillation
D. Crystallization
145. Which of the following is a reducing agent?
A. Oxygen
B. Hydrogen
C. Chlorine
D. Fluorine
146. The chemical formula of baking soda is:
A. Na₂CO₃
B. NaHCO₃
C. CaCO₃
D. NaOH
147. Which of the following is an alkaline earth metal?
A. Sodium
B. Potassium
C. Calcium
D. Aluminum
148. The percentage of oxygen in air is approximately:
A. 21%
B. 78%
C. 50%
D. 10%
149. Which gas turns lime water milky?
A. Oxygen
B. Hydrogen
C. Carbon dioxide
D. Nitrogen
150. The study of carbon compounds is called:
A. Physical chemistry
B. Organic chemistry
C. Analytical chemistry
D. Inorganic chemistry
151. Which of the following is used to test the presence of starch?
A. Benedict’s solution
B. Iodine solution
C. Lime water
D. Litmus paper
152. The functional group of alcohols is:
A. –COOH
B. –OH
C. –CHO
D. –NH₂
153. Which element has atomic number 11?
A. Magnesium
B. Sodium
C. Aluminum
D. Potassium
154. Which of the following is a non-metal?
A. Copper
B. Iron
C. Sulfur
D. Zinc
155. The formula of calcium carbonate is:
A. CaO
B. Ca(OH)₂
C. CaCO₃
D. CaCl₂
156. Which process separates components based on boiling points?
A. Filtration
B. Distillation
C. Sedimentation
D. Sublimation
157. The smallest particle of an element retaining its properties is:
A. Molecule
B. Atom
C. Ion
D. Compound
158. Which gas is essential for respiration?
A. Nitrogen
B. Carbon dioxide
C. Oxygen
D. Hydrogen
159. Which of the following is an example of a physical change?
A. Rusting
B. Burning
C. Melting
D. Digestion
160. The formula of nitric acid is:
A. HNO₃
B. H₂SO₄
C. HCl
D. CH₃COOH
161. Which scientist proposed the periodic table?
A. Rutherford
B. Dalton
C. Mendeleev
D. Bohr
162. Which of the following is a diatomic molecule?
A. Helium
B. Neon
C. Oxygen
D. Argon
163. The charge on an electron is:
A. Positive
B. Neutral
C. Negative
D. Double positive
164. Which of the following is a base?
A. HCl
B. H₂SO₄
C. NaOH
D. CO₂
165. The gas used in balloons is:
A. Oxygen
B. Nitrogen
C. Helium
D. Chlorine
166. The formula of methane is:
A. CH₄
B. C₂H₆
C. C₃H₈
D. C₂H₄
167. Which of the following is a chemical change?
A. Freezing water
B. Boiling water
C. Burning paper
D. Dissolving sugar
168. Which metal is extracted from bauxite?
A. Iron
B. Copper
C. Aluminum
D. Zinc
169. The process of removing impurities from water is called:
A. Filtration
B. Purification
C. Distillation
D. Sedimentation
170. Which of the following is used as fuel in rockets?
A. Hydrogen
B. Nitrogen
C. Oxygen
D. Chlorine
171. Which compound is commonly known as table salt?
A. Sodium carbonate
B. Sodium chloride
C. Potassium chloride
D. Calcium carbonate
172. Which acid is used in car batteries?
A. Hydrochloric acid
B. Nitric acid
C. Sulfuric acid
D. Acetic acid
173. The chemical symbol of potassium is:
A. Po
B. Pt
C. P
D. K
174. Which gas is produced during photosynthesis?
A. Carbon dioxide
B. Nitrogen
C. Oxygen
D. Hydrogen
175. The formula of ethanol is:
A. CH₃OH
B. C₂H₅OH
C. CH₄
D. C₃H₇OH
176. Which element is essential for making stainless steel?
A. Sodium
B. Chromium
C. Calcium
D. Sulfur
177. The process by which plants lose water vapor is:
A. Respiration
B. Photosynthesis
C. Transpiration
D. Digestion
178. Which of the following is an example of a saturated hydrocarbon?
A. Ethene
B. Ethyne
C. Benzene
D. Ethane
179. Which substance is used to neutralize acidic soil?
A. HCl
B. NaOH
C. Lime
D. Vinegar
180. Which gas is responsible for acid rain?
A. Oxygen
B. Sulfur dioxide
C. Hydrogen
D. Helium
181. Which type of reaction releases energy?
A. Endothermic
B. Exothermic
C. Reversible
D. Neutralization
182. The formula of quick lime is:
A. CaCO₃
B. CaO
C. Ca(OH)₂
D. CaCl₂
183. Which of the following is a transition metal?
A. Sodium
B. Magnesium
C. Iron
D. Calcium
184. Which gas is used in welding?
A. Carbon dioxide
B. Oxygen
C. Acetylene
D. Nitrogen
185. The atomic number of carbon is:
A. 4
B. 6
C. 8
D. 12
186. Which element is used in thermometers?
A. Iron
B. Mercury
C. Copper
D. Sodium
187. The formula of slaked lime is:
A. CaO
B. Ca(OH)₂
C. CaCO₃
D. NaOH
188. Which process converts liquid into gas?
A. Freezing
B. Condensation
C. Evaporation
D. Sublimation
189. Which of the following is a halogen?
A. Neon
B. Chlorine
C. Argon
D. Sodium
190. The major component of natural gas is:
A. Ethane
B. Propane
C. Methane
D. Butane
191. Which of the following is an amphoteric oxide?
A. Na₂O
B. MgO
C. Al₂O₃
D. CO₂
192. The pH of human blood is approximately:
A. 2.0
B. 5.5
C. 7.4
D. 10.0
193. Which gas is used in photosynthesis?
A. Oxygen
B. Carbon dioxide
C. Nitrogen
D. Hydrogen
194. Which instrument is used to measure pH?
A. Thermometer
B. Barometer
C. pH meter
D. Ammeter
195. Which of the following is an ore of iron?
A. Bauxite
B. Hematite
C. Galena
D. Zinc blende
196. Which of the following is a covalent compound?
A. NaCl
B. MgO
C. H₂O
D. KCl
197. Which gas is commonly known as marsh gas?
A. Ethane
B. Propane
C. Methane
D. Butane
198. The formula of bleaching powder is:
A. CaOCl₂
B. NaCl
C. HCl
D. CaCO₃
199. Which process is used to obtain pure crystals from a solution?
A. Filtration
B. Crystallization
C. Sublimation
D. Distillation
200. Which branch of chemistry deals with the speed of chemical reactions?
A. Organic chemistry
B. Physical chemistry
C. Biochemistry
D. Chemical kinetics