in reaction a + b → c, 6 g of reactant b was used, and 15 g of product c was produced. what mass of reactant…

in reaction a + b → c, 6 g of reactant b was used, and 15 g of product c was produced. what mass of reactant a was used? a 6 g b 21 g c 9 g d 15 g

in reaction a + b → c, 6 g of reactant b was used, and 15 g of product c was produced. what mass of reactant a was used? a 6 g b 21 g c 9 g d 15 g

Answer

Answer:

C. 9 g

Explanation:

Step1: Apply law of conservation of mass

According to the law of conservation of mass, the total mass of reactants equals the total mass of products in a chemical - reaction. Let the mass of reactant A be $m_A$, the mass of reactant B be $m_B = 6g$, and the mass of product C be $m_C=15g$. So, $m_A + m_B=m_C$.

Step2: Solve for $m_A$

Rearrange the equation $m_A + m_B=m_C$ to get $m_A=m_C - m_B$. Substitute $m_B = 6g$ and $m_C = 15g$ into the equation: $m_A=15g - 6g=9g$.