The answer is: [C]: "4" .
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Note: To balance this equation, the coefficient, "4", should be placed in front of the PCl₃ ; and the coefficient, "6", should be placed in front of the Cl₂ .
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The balanced equation is:
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P₄ (s) + 6 Cl₂ (g) <span>→ 4 </span>PCl₃ (l) .
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Answer:
The first law states that if the net force is zero, then the velocity of the object is constant.