Answer:
+4
Step-by-step explanation:
I think if one proton has+1charge four protons may have+4charges
Answer:
so sorry i needed the points to ask my question.
Step-by-step explanation:
x = liters of 40% solution
y = liters of 70% solution
Gabe needs 30 liters, so
x + y = 30
Each liter of 40% solution contributes 0.4x liter of acid; each liter of 70% solution contributes 0.7y liter of acid. Gabe needs a solution with concentration 60%, which from 30 liters amounts to a net volume of 0.6*30 = 18 liters of acid. So
0.4x + 0.7y = 18
Solve the system however you like. By substitution, we have
y = 30 - x
0.4x + 0.7(30 - x) = 18
0.4x + 21 - 0.7x = 18
3 = 0.3x
==> x = 10 ==> y = 20