Answer:
50
Step-by-step explanation:
to get the unit per hour, you have to divide the amout, which is 350, by the time, which is 7, and you get 50
formula: gram of solute/gram of solution X 100
so 150/400 X 100 is <u>3</u><u>7</u><u>.</u><u>5</u><u>%</u><u> </u><u>of</u><u> </u><u>KNO3</u>
∵
∴