I need some help on these chemsitry questions. 1) A nonelectrolyte is a solution
ID: 899144 • Letter: I
Question
I need some help on these chemsitry questions.
1) A nonelectrolyte is a solution that contains ____.
a. ions b. molecular solutes c. free electrons d. charged colloids
(I chose B?)
2) Metalic silver, Ag, is placed in a solution of manganese (II) nitrate, Mn(NO3)2. Does a reaction occur, and if so, what are the products?
a. No b. Yes, Ag+ and Mn c. Yes, Ag+ and Mn+ d. Yes, Ag and Mn
(I looked at my reactivity chart and saw that silver could oxidize manganese, but I got scared and confused so I just chose A. Also, I didn't know how to work out the charges.)
3) A 2.00 M solution of K2SO4 is prepared. The solution is ____M in K+ and ____M in SO42-.
a. 1.00, 1.00 b. 2.00, 2.00 c. 1.00, 4.00 d. 4.00, 2.00
(I chose D, because the proportions seemed right. I thought - which was probably wrong - that for every 1 mole of SO42- that you needed 2 moles of K+. So with my 2:1 ratio only answer D fit my thinking.)
4) 35.0 mL of a 6.00 M solution of HNO3 are diluted to a final volume of 500.00 mL. The second (more dilute) solution has a concentration of ____M.
a. 5.83 b. 0.420 c. 2.380 d. 0.600
(I chose B, because I used the C1V1=C2V2 forumla; (35.0)(6.00) = C2(500) which I solved C2 = .420 M. Did I use the right forumla to get the answer or did I just get lucky?)
5) Iron (Fe) has a specific heat of 0.450 J/g-C. It takes ____ of heat to raise the temperature of 50.0g of Fe 25.0 C.
a. 563 J b. 5.62 kJ c. 11.3 kJ d. 4.44 kJ
(I got answer A. I set up my equation q= (.450J/g-C)(50.0g)(25.0C) = 526.5 J = 563 J = .563 kJ. Answer A was actually something I calculated, and I calculated to .563 kJ just to see if I accidentally calcauted answer B. I chose A, thouh. Is this right?)
6) A reaction has a theoretical yield of 5.84g of prodct, but a percent yield of only 68.5%. What is the actual yield?
a. 3.80g b. 11.6g c. 8.98g d. 4.00g
(I chose answer D. I just used a simple proportional fraction equation. Is this the correct answer?)
Thank you!
Explanation / Answer
I need some help on these chemsitry questions.
1) A nonelectrolyte is a solution that contains ____.
a. ions b. molecular solutes c. free electrons d. charged colloids
its the only that makes sense, ions will conduct electricity and free electrons will be an aelocrotlyte. Charged colloids has nothing to do with this
2) Metalic silver, Ag, is placed in a solution of manganese (II) nitrate, Mn(NO3)2. Does a reaction occur, and if so, what are the products?
a. No b. Yes, Ag+ and Mn c. Yes, Ag+ and Mn+ d. Yes, Ag and Mn
(I looked at my reactivity chart and saw that silver could oxidize manganese, but I got scared and confused so I just chose A. Also, I didn't know how to work out the charges.)
you are correct, Ag is very stable and has no need to share its electrons with NO3- ... Mn+2 will remain with its +2 charge
3) A 2.00 M solution of K2SO4 is prepared. The solution is ____M in K+ and ____M in SO42-.
a. 1.00, 1.00 b. 2.00, 2.00 c. 1.00, 4.00 d. 4.00, 2.00
(I chose D, because the proportions seemed right. I thought - which was probably wrong - that for every 1 mole of SO42- that you needed 2 moles of K+. So with my 2:1 ratio only answer D fit my thinking.)
Correct, there is 2 mol of K+ thereofre expect 4... same case with SO4-
4) 35.0 mL of a 6.00 M solution of HNO3 are diluted to a final volume of 500.00 mL. The second (more dilute) solution has a concentration of ____M.
a. 5.83 b. 0.420 c. 2.380 d. 0.600
(I chose B, because I used the C1V1=C2V2 forumla; (35.0)(6.00) = C2(500) which I solved C2 = .420 M. Did I use the right forumla to get the answer or did I just get lucky?)
You used the right formula. Dilution formula is always valid when no reaction takes place
5) Iron (Fe) has a specific heat of 0.450 J/g-C. It takes ____ of heat to raise the temperature of 50.0g of Fe 25.0 C.
a. 563 J b. 5.62 kJ c. 11.3 kJ d. 4.44 kJ
(I got answer A. I set up my equation q= (.450J/g-C)(50.0g)(25.0C) = 526.5 J = 563 J = .563 kJ. Answer A was actually something I calculated, and I calculated to .563 kJ just to see if I accidentally calcauted answer B. I chose A, thouh. Is this right?)
True, you are correct. Dont confuse kJ or J and 10^3 multiples
6) A reaction has a theoretical yield of 5.84g of prodct, but a percent yield of only 68.5%. What is the actual yield?
a. 3.80g b. 11.6g c. 8.98g d. 4.00g
(I chose answer D. I just used a simple proportional fraction equation. Is this the correct answer?)
By definition %yield = real / theoretical * 100%
if you get 68.5%
then
68.5% = real/5.84g 100%
0.685 = real / 5.84
real = 4g which is d
You are correct