All categories

3 years ago

What is this equivalent to -k+3k

Chemistry

2 answers:

Artemon [7]3 years ago

3 0

Answer:

Explanation:

____ [38]3 years ago

3 0

Answer:

+2k

Explanation:

Because +++k and -k answer is ++k

One +Cancel with -

You might be interested in

In a certain industrial process involving a heterogeneous catalyst, the volume of the catalyst (in the shape of a sphere) is 10.

trasher [3.6K]

Answer:

The second run will be faster - true, the increased surface area of catalyst will increase the rate of reaction

The second run will have the same rate as the first - possible, in case there is a factor other than catalyst limiting the reaction

The second run has twice the surface area - yes, 44 sqcm to 22 sqcm

Explanation:

A catalyst is a material which speeds up a reaction without being consumed in the process. A heterogeneous catalyst is one which is of a different phase than the reactants. The effectiveness of a catalyst is dependent on the available surface area. The first step for this question is to determine the total available surface area of catalyst in both processes.

Step 1: Determine radius of large sphere

$V_{L}=\frac{4}{3}*pi*{r_{L}}^{3}$

$10=\frac{4}{3}*pi*{r_{L}}^{3}$

${r_{L}}^{3}=\frac{7.5}{pi}$

$r_{L}=1.337cm$

Step 2: Determine surface area of large sphere

$A_{L}=4*pi*{r_{L}}^{2}$

$A_{L}=4*pi*1.337^{2}$

$A_{L}=22.463 cm^{2}$

Step 3: Determine radius of small sphere

$V_{s}=\frac{4}{3}*pi*{r_{s}}^{3}$

$1.25=\frac{4}{3}*pi*{r_{s}}^{3}$

${r_{s}}^{3}=\frac{0.9375}{pi}$

$r_{s}=0.668cm$

Step 4: Determine surface area of small sphere

$A_{s}=4*pi*{r_{s}}^{2}$

$A_{s}=4*pi*0.668^{2}$

$A_{s}=5.607 cm^{2}$

Step 5: Determine total surface area of 8 small spheres

$A_{S}=8*A_{s}$

$A_{S}=8*5.607$

$A_{S}=44.856 cm^{2}$

$A_{L}=22.463 cm^{2}$ - Surface area of 1 large sphere

$A_{S}=44.856 cm^{2}$ - Surface area of 8 small spheres

Options:

The second run will be faster - true, the increased surface area of catalyst will increase the rate of reaction
The second run will be slower - false, the increased surface area of catalyst will increase the rate of reaction
The second run will have the same rate as the first - possible, in case there is a factor other than catalyst limiting the reaction
The second run has twice the surface area - yes, 44 sqcm to 22 sqcm
The second run has eight times the surface area - no, 44 sqcm to 22 sqcm
The second run has 10 times the surface area - no, 44 sqcm to 22 sqcm

7 0

3 years ago

Read 2 more answers

What is the answer to question 7, NH4C2H3O2

Sliva [168]

The answer is Ammonium acetate

4 0

3 years ago

Read 2 more answers

Salt water can be desalinated by distillation. How much energy is needed to convert 175 g of salt water at 28.0 °C to water vapo

Vinil7 [7]

Answer:

$\Delta H=4.63x10^{5}J=463kJ$

Explanation:

Hello,

In this case, we find the following states:

a. Liquid salt water at 28.0 °C.

b. Liquid salt water at 102.5 °C.

c. Vapor salt water at 102.5 °C.

The first process (1) is to heat the liquid water from 28.0 °C to 102.5 °C and the second one (2) to vaporize the liquid salt water. In such a way, each process has an amount of energy that when added, yields the total energy for the process as shown below:

$\Delta H=\Delta H_1+\Delta H_2\\\Delta H=mCp\Delta T+m\Delta _VH\\\Delta H=175g*5.19\frac{J}{g*K}*(375.65K-301.15K)+175g*2.26\frac{kJ}{g} *\frac{1000J}{1kJ} \\\Delta H=4.63x10^{5}J=463kJ$

Best regards.

4 0

3 years ago

A bird sits on her eggs to keep them warm

Troyanec [42]

Answer:

This would be Conduction

Explanation:

Conduction is the transfer of heat between two surfaces in contact with each other like the bird and the eggs.

5 0

3 years ago

What does it regulate? One sentence will help!

Mandarinka [93]

<span>a regultate is to control or direct by a rule, principle, or method.</span>

7 0

3 years ago

What is this equivalent to -k+3k​

What is this equivalent to -k+3k