Question

HELP QUICK!! I MEDAL!!!!

Answer 1

13. Which of the following compounds does not form a precipitate when reacted with sodium hydroxide?
A.Cu(NO3)2
b. FeSO4
c. NaNO3
d. Fe(NO3)3

Answer 2

14. What is the formula mass (molar mass) of cholesterol (C27H46O), a fat found in your blood and cell membranes?
A. 386 g/mol
B. 260 g/mol
C. 130 g/mol
D. 29 g/mol

Answer 3

15. Look at the following hypothetical reaction: A + 3B C + 3D. Assume that the equation is balanced. Which of the following mole ratios will produce the most product?
A. A/B
B. 2A/B
C. A/3B
D. 3A/B

Answer 4

17. Which of the following would cause the percent yield of a reaction to be less than 100%?
A. A balanced chemical equation is used.
B. Pure reactants are used
C. The product participates in a side reaction
D. All of the limiting reagent gets used up

Answer 5

@amistre64 @SolomonZelman @Abhisar @iambatman @aaronq @kelliegirl33 @radar @Loser66 @Banes @Hoslos

Answer 6

i have more if i can get help with these ones

Answer 7

@uri @Mimi_x3

Answer 8

Hello,

I can assist on question 14. Do you know how to get the molar mass of an element?

Answer 9

nope

Answer 10

i have like 15 min before 55 questions have to be turned in

Answer 11

#14 i figured it out it is a

Answer 12

You can get the molar mass of an element by looking at the periodic table of elements.

Look at how one gets the molar mass of an element: http://www.kmacgill.com/lecture_notes/lecture_notes_9_files/image012.gif

Molar mass of an elements is the atomic mass.
To get the molar mass of a compound you, simply have to find the sum.
\[C_{27}H_{46}O_{1}\]
\(12.011 \times 27 = ... etc\)
This results in \(386.654 g/mol\) (Grams per mole).

Answer 13

@Clalgee @radar @geerky42 @aaronq @AlexandervonHumboldt2 @Coolsector @kio @Kim21 @leonardo0430 @LiteNing1337 @love10129151 @mathstudent55

Answer 14

yes i already got it

Answer 15

@physo

Answer 16

Okay, I will take question 13 then. A precipitate is a product formed from a chemical reaction which is NOT soluble in water.

Group 1 of the periodic table of elements, are soluble by rule of thumb. (If I remember correctly.) Since \(NaNO_{3}\) contains \(Na+\) no precipitate will form.

Answer 17

ok thanks, can you help me with all of them??

Answer 18

19. The law of multiple proportions accounts for which of the following?
A. subscripts in chemical formulas
B. coefficients in chemical formulas
C. coefficients in chemical equations
D. direction of the arrow in chemical equations

Answer 19

@Algorithmic PLZ HELP WITH MORE

Answer 20

Sorry, I really do not dabble with much chemistry. If I recall correctly on question 17, once the limiting agent is used up the reaction stops. When a side reaction occurs it is generally unwanted chemical reaction, because it diminishes the yield of the desired product.

Answer 21

yes it is like if you have 2 eggs and one brownie recipie but the brownie thing calls for three eggs the eggs are the limiting factor, thats an example from my teacher but once i am giving the equation idk

Answer 22

For question 15, the equation seems malformed. I take you mean: \(A + 3B \longrightarrow C + 3D\).

If so, we are told to assume that the equation is balanced. Which of the following mole ratios will produce the most product?
It turns into a word problem from there, 1 Mole of A needs 3 Moles of B, ergo A/3B.Is the ideal mole ratio.

Do you understand my reasoning on question 17?

Answer 23

kinda but not really, and yes thats what the equation was

Answer 24

@Algorithmic

Answer 25

For 13, I would say A, becauuse Cu( oH)2 is a base not a precipitate.

Answer 26

14, simply sum the masses 12 *27+46+16=386