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اجازة سعيدة للكل ..
استاذتي عندي اسئلة بالشابتر الرابع .. تقول

what mass of K2CO3 is neede to prepare 200.mL of solution having a potassium ion concentration of 0,150 M ?

A. 4.15
B. 10.4
C. 13.8
D. 2.07
E. 1.49
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85. 25.0 mL of a 0.2450 M NH4Cl solution is added to 55.5 mL of
0.1655 M FeCl3. What is the concentration of chloride ion in the final solution?
A. 0.607 M
B. 0.418 M
C. 1.35 M
D. 0.190 M
E. 0.276 M
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90. Reaction of 1.00 mole CH4 with excess Cl2 yields 96.8 g CCl4. What is the percent yield of CCl4 ?(Atomic weights: C = 12.01, Cl = 35.45).
CH4 + 4 Cl2 CCl4 + 4 HCl
A. 64.3
B. 57.3
C. 65.9
D. 62.9