Answer:
Reactants: K = 2, S = 1, Co = 1, Cl = 2; Products: K = 2, S = 1, Co = 1, Cl = 2
Explanation:
The reaction is a double replacement reaction so the anions (Cl⁻ and S²⁻) switch places.
<u>1</u> K₂S + <u>1</u> CoCl₂ ⇒ <u>2</u> KCl + <u>1 </u>CoS (balanced chemical equation)
On the reactants and products side, K = 2, S = 1, Co = 1, and Cl = 2.
Hope that helps.
The correct answer is A. <span>167 milliliters of 7% solution and 333 milliliters of 4% solution and here is how:
</span><span>If x is the number of milliliters of the 7% saline solution and y is the number of milliliters of the 4% saline solution then add up to 500 milliliters total, so x + y = 500.
</span>and if we do
x + y = 500
<span>x = 500 - y </span>
<span>0.07x + 0.04y = 25 (substitute 500 - y for x) </span>
<span>0.07(500 - y) + 0.04y = 25 </span>
<span>35 - 0.07y + 0.04y = 25 </span>
<span>-0.03y + 35 = 25 </span>
<span>-0.03y = -10 </span>
<span>y = 333.333... </span>
<span>y = about 333 </span>
<span>x = 500 - y = 500 - 333 = 167
</span>Then you know why the answer is A.