شرح للكيمياء و أسئلة مراجعة

[فراولة حمراء]

ممكن خطوات حل تست بانك شابتر 4 ..

1. What mass of K2CO3 is needed to prepare 200. mL of a solution having a potassium ion concentration of 0.150 M?

A. 4.15 g
B. 10.4 g
C. 13.8 g
D. 2.07 g
E. 1.49 g


2. A 50.0 mL sample of 0.436 M NH4NO3 is diluted with water to a total volume of 250.0 mL. What is the ammonium nitrate concentration in the resulting solution?

A. 21.8 M
B. 0.459 M
C. 2.18  10-2 M
D. 8.72  10-2 M
E. 0.109 M



3. How many milliliters would you need to prepare 60.0 mL of 0.200 M HNO3 from a stock solution of 4.00 M HNO3?
A. 60 mL
B. 240 mL
C. 24 mL
D. 1000 mL
E. 48 mL

ما أعرف ليش .. انا متأكده من الخطوات بس مابيطلع الناتج صح =(