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HESI A2 Chemistry (V1) Questions and Answers | Latest Version | 2025/2026 | Correct & Verified
What type of reaction releases energy in the form of heat or light?✔✔Exothermic reaction
What type of reaction absorbs energy from the surroundings?✔✔Endothermic reaction
What is the main solvent in living systems?✔✔Water
What type of bond holds water molecules together?✔✔Hydrogen bond
What is the mass of one mole of oxygen gas (O₂)?✔✔32 g
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How many atoms are in one mole of a substance?✔✔6.022 × 10²³ atoms
What is the formula for density?✔✔Mass ÷ Volume
What is the smallest particle of an element that retains its chemical properties?✔✔Atom
What is the charge of a proton?✔✔Positive
What is the charge of an electron?✔✔Negative
What is the charge of a neutron?✔✔Neutral
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What is the atomic number of carbon?
✔✔6
What is the atomic mass of an element equal to?✔✔The sum of protons and neutrons
What is formed when two or more atoms bond together?✔✔Molecule
What type of bond involves the sharing of electrons?✔✔Covalent bond
What type of bond involves the transfer of electrons?✔✔Ionic bond
What is the pH of a neutral solution at 25°C?
✔✔7
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