PRELIMINARY STAGE 2024
Archbishop Porter Girls' SHS: 45 points (Winner, qualified to the one-eighth stage)
Ejisuman SHS: 32 points
Wenchi Methodist SHS: 26 points
ROUND 4 - TRUE OR FALSE
QUESTION
1. According to Dalton's atomic theory, compounds are formed when atoms of an element combine in fixed simple whole number ratios.
ANSWER: FALSE
EXPLANATION:
Dalton's theory states that compounds are formed when atoms of different elements combine in fixed simple whole number ratios, not atoms of the same element.
2. According to Dalton's atomic theory, isotopes are different forms of the same element with different masses.
ANSWER: FALSE
EXPLANATION:
Dalton's atomic theory does not account for isotopes; it explicitly states that all atoms of a given element are identical in mass and properties.
3. According to Dalton's atomic theory, neutral atoms of the same element have the same number of electrons as protons.
ANSWER: FALSE
EXPLANATION:
Dalton's atomic theory was formulated before the discovery of subatomic particles, so it makes no mention of protons, electrons, or neutrons.
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PRACTICE QUESTIONS
1. QUESTION: According to Dalton's atomic theory, atoms cannot be divided into smaller particles.
ANSWER: TRUE
EXPLANATION:
Dalton treated atoms as indivisible; subatomic particles were discovered later.
2. QUESTION: According to Dalton's atomic theory, atoms of the same element can have different masses.
ANSWER: FALSE
EXPLANATION:
Dalton held that all atoms of a given element are identical in mass; isotopes were unknown to him.
3. QUESTION: According to Dalton's atomic theory, atoms are rearranged, not created or destroyed, in a chemical reaction.
ANSWER: TRUE
EXPLANATION:
This postulate explains the law of conservation of mass.
4. QUESTION: According to Dalton's atomic theory, atoms of different elements combine in simple whole-number ratios to form compounds.
ANSWER: TRUE
EXPLANATION:
This postulate explains the law of definite proportions.
5. QUESTION: According to Dalton's atomic theory, an atom consists of a nucleus surrounded by electrons.
ANSWER: FALSE
EXPLANATION:
Dalton's atoms had no inner structure; the nucleus came from Rutherford's work.
6. QUESTION: According to Dalton's atomic theory, atoms of one element can be changed into atoms of another element in a chemical reaction.
ANSWER: FALSE
EXPLANATION:
Dalton held that atoms keep their identity in chemical reactions.