1 George is learning about the classification of carbohydrates. He knows that carbohydrates can be simple or complex. Which of the following is a simple carbohydrate? A Starch B Glucose C Cellulose D Glycogen
2 Ahmed is studying the enthalpy of reaction. He determines that the reaction A → B has ΔH = +100 kJ. What type of reaction is this? A Exothermic B Endothermic C Thermoneutral D Spontaneous
3 Xia is studying the combustion of alkanes. She knows that alkanes burn with a clean flame when complete combustion occurs. What color is the flame of complete combustion? A Blue B Yellow C Red D Green
4 Julia is studying dynamic equilibrium. She learns that at equilibrium, the reaction has not ceased. Which of the following statements is true at equilibrium? A The forward reaction is faster B The reverse reaction is faster C Both reactions have stopped D Both reactions occur at the same rate
5 Xia is studying the functional group of amines. She learns that amines contain a nitrogen atom bonded to carbon groups. Which of the following is a primary amine? A Methylamine B Dimethylamine C Trimethylamine D Aniline
6 Lara is studying the dehydrogenation of alkanes to alkenes. She knows that ethane can be converted to ethene. What is the type of reaction? A Oxidation B Reduction C Dehydrogenation D Halogenation
7 Ibrahim is learning about proteins. He knows that proteins are essential for growth and repair. What is the basic building block of proteins? A Nucleotides B Amino acids C Fatty acids D Monosaccharides
8 The main purpose of electroplating is to: A Increase weight B Prevent corrosion and enhance appearance C Reduce conductivity D Increase rusting
10 Air pollution mainly affects: A Only plants B Only animals C Human health and environment D Only atmosphere
11 Julia is studying electronegativity. She knows it is the ability of an atom to attract electrons in a chemical bond. As we move across a period from left to right, electronegativity generally: A Decreases B Increases C Stays the same D First increases then decreases
12 Hina is collecting data on the temperature of a reaction. She records the temperature every 30 seconds. What is the time interval between measurements called? A Sampling interval B Data range C Measurement precision D Calibration period
13 Equilibrium constant is a measure of: A Rate of reaction B Extent of reaction C Speed of reaction D Time of reaction
14 Bilal is doing an experiment with a substance that takes the shape of its container but has a definite volume. He pours it from a beaker into a graduated cylinder, and it flows easily. What state of matter is Bilal working with? A Solid B Liquid C Gas D Plasma
15 Xia is learning about air quality indices. She understands that the AQI is used to communicate air quality. What does a higher AQI indicate? A Better air quality B Worse air quality C No change in air quality D No information
19 Ahmed is balancing the equation: Na + Cl2 → NaCl. What is the correct balanced equation? A 2Na + Cl2 → 2NaCl B Na + Cl2 → NaCl C Na + 2Cl2 → NaCl2 D 2Na + 2Cl2 → 2NaCl
20 Yara is studying corrosion prevention methods. She learns that coating with paint is a simple and effective method. Which of the following is an advantage of painting to prevent corrosion? A It makes the metal magnetic B It provides a barrier to moisture and oxygen C It increases the metal's electrical conductivity D It makes the metal transparent
21 Aisha is studying smoking as a risk factor. She learns that smoking contributes to indoor air pollution. What harmful substance is released in cigarette smoke? A Oxygen B Carbon monoxide C Nitrogen D Water vapor
22 Uma is learning about the concept of acids and bases. She knows that according to the Arrhenius concept, acids produce H+ ions in water. Which of the following is an Arrhenius acid? A H2SO4 B NaOH C NH3 D NaCl
23 Julia is conducting an experiment and wants to ensure that her data is valid. What does validity in experimental data refer to? A How close the data is to the true value B The consistency of the data C Whether the data measures what it is supposed to measure D The amount of data collected
24 Tina is studying the properties of halogens. She notes that the color of halogens becomes darker as we move down the group. What is the color of iodine at room temperature? A Pale yellow gas B Greenish-yellow gas C Red-brown liquid D Grey-black solid
25 Hydrogen bonding occurs when hydrogen is bonded with: A Carbon B Nitrogen, oxygen or fluorine C Sulfur D Chlorine
26 Quinn is studying ways to deal with water pollution. He knows that planting trees can help. How does planting trees help in reducing water pollution? A By increasing runoff B By reducing soil erosion and runoff of pollutants C By decreasing water availability D By increasing fertilizer use
27 Usman is studying acid rain mitigation. He learns that adding limestone to lakes can neutralize acidity. What is the purpose of adding limestone to acidified lakes? A To increase acidity B To neutralize acid and raise pH C To add nutrients D To kill algae
28 Usman is learning about dynamic equilibrium. He understands that at equilibrium, the rates of the forward and reverse reactions are equal. What does this imply about the concentrations of reactants and products? A They are increasing B They are decreasing C They are constant D They are fluctuating
29 Usman is studying metallic bonds. He learns that metals have a 'sea of delocalized electrons'. What is the characteristic of metallic bonding that explains the conductivity of metals? A Presence of free ions B Presence of a sea of free electrons C Presence of covalent bonds D Presence of ionic bonds
30 Heat change measured at constant pressure is: A Internal energy B Enthalpy change C Entropy D Activation energy