The temperature will decrease the rate of reactions.

Many double-displacement reactions are enzyme-catalyzed via the "ping pong" mechanism, so called because the reactants appear to

zhenek [66]

Answer:

D. It will decrease by a factor of 4

Explanation:

According to the question , the equation follows :

$A+B\rightarrow C+D$

Rate law : This states the rate of reaction is directly proportional to concentration of reactants with each reactant raised to some power which may or may not be equal to the stoichiometeric coefficient.

$Rate\ \alpha [A]^{a}[B]^{b}$

$r=[A]^{a}[B]^{b}$ .................(1)

STEP": First, find out the power "a" and "b"

a+b = 3 (because it is given that the reaction follow 3rd order-kinetics)

According to question, doubling the concentration of the first reactant causes the rate to increase by a factor of 2 means,

r' = 2r if [A'] = 2[A]

Here [B] is uneffected means [B']=[B]

hence new rate =

$r'=[A']^{a}[B']^{b}$

Put the value of [A'] , [B'] and r' in the above equation:

$2r=[2A]^{a}[B]^{b}$ ...........(2)

Divide equation (1) by (2) we , get

$\frac{2r}{r}=\frac{[2A]^{2}[B]^{b}}{[A]^{a}[B]^{b}}$

$2= 2(\frac{A}{A})^{a}\times (\frac{B}{B})^{b}$

Here A and A cancel each other

B and B cancel each other

We get,

$2= 2^{a}\times 1^{b}$

1^b = 1 ( power of 1 = 1)

$2= 2^{a}$

This is possible only when a = 1

We know that : a + b = 3

1 + b = 3

b =3 -1 = 2

b = 2

Hence the rate law becomes :

$r=[A]^{a}[B]^{b}$

$r=[A]^{1}[B]^{2}$ .............(3)

Look in the question now, it is asked to calculate the concentration of [B],if cut in half

Hence

[B']=1/2[B]

Insert the value of [B'] in equation (3)

$r'=[A]^{1}[B']^{2}$

$r'=[A]^{1}(\frac{1}{2}[B])^{2}$

$r'=\frac{1}{4}[A]^{1}[B]^{2}$ ............(a)

But

$r=[A]^{a}[B]^{b}$ ..............(b)

Compare equation (a) and (b) , we get

new rate r' =

r' = 1/4 r

7 0

3 years ago

Which of the following molecule(s) is (are) polar? CO2, CH4, CBr4, or CHBr3

PolarNik [594]

CO2 is not polar as in this case the same types of molecules are pulling in the same as well as opposite direction. CH4 is also not polar as there is no imbalance in the charge of the molecules. CBr4 is also not polar because in this case also no imbalance in the molecular charges can be seen. CHBr3 is a bit polar in nature because it has different kind of charges at its opposite ends. S among the all 4 options CHBr3 is polar.

4 0

3 years ago

What attractive force pulls electrons toward protons to form chemical bonds?

ehidna [41]

Answer:

C). Electronegativity.

Explanation:

'Electronegativity' is described as the tendency or a measure of the ability of an atom or molecule to attract electrons that leads to the formation of chemical bonds. It is denoted by 'χ', a Greek letter. The elements like Fluorine having a very high rate of electronegativity, its atom would attract the electrons more strongly while the elements with lesser electronegativity like Cesium would possess a lesser tendency to attract electrons towards it in order to form a bond. Thus, option C is the correct answer.

6 0

3 years ago

30 points!!!

madam [21]

C, Fuel cell cars do not release greenhouse gases, is the best choice. Hydrogen fuel cells do not release carbon dioxide.

5 0

4 years ago

Read 2 more answers

Simplify the ratio 32:21 in its simplest form ..show your working

makvit [3.9K]

Answer:

32/21

Explanation:

Find the GCD (or HCF) of numerator and denominator. GCD of 32 and 21 is 1.

32 ÷ 121 ÷ 1.

Reduced fraction: 3221. Therefore, 32/21 simplified to lowest terms is 32/21.

8 0

3 years ago