1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Gelneren [198K]
2 years ago
13

Please help Show your work

Chemistry
1 answer:
Yuliya22 [10]2 years ago
6 0

Answer:

21

Explanation: 2+1=21

You might be interested in
How are distillation and reverse osmosis alike?
Andrei [34K]
I'm having trouble with this one. At the very least, they both purify water. If I'm not mistaken, distillation is part of the process of purifying water.
Really sorry, I hope I helped at least a little! If you have any other questions I might be able to answer better, let me know..
5 0
3 years ago
What is the theoretical yield of Calcium if we begin with 12.6 grams of Aluminium?
AlladinOne [14]

The question is incomplete, here is the complete question:

The given chemical reaction is:

2Al+3Cu(NO_3)_2\rightarrow 3Cu+2Al(NO_3)_3

What is the theoretical yield of Calcium if we begin with 12.6 grams of Aluminium?

<u>Answer:</u> The theoretical yield of copper is 44.48 grams

<u>Explanation:</u>

To calculate the number of moles, we use the equation:

\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}     .....(1)

Given mass of aluminium = 12.6 g

Molar mass of aluminium = 27 g/mol

Putting values in equation 1, we get:

\text{Moles of aluminium}=\frac{12.6g}{27g/mol}=0.467mol

The given chemical equation follows:

2Al+3Cu(NO_3)_2\rightarrow 3Cu+2Al(NO_3)_3

By Stoichiometry of the reaction:

2 moles of aluminium produces 3 moles of copper

So, 0.467 moles of aluminium will produce = \frac{3}{2}\times 0.467=0.7005mol of copper

Now, calculating the mass of copper  from equation 1, we get:

Molar mass of copper = 63.5 g/mol

Moles of copper = 0.7005 moles

Putting values in equation 1, we get:

0.7005mol=\frac{\text{Mass of copper}}{63.5g/mol}\\\\\text{Mass of copper}=(0.7005mol\times 63.5g/mol)=44.48g

Hence, the theoretical yield of copper is 44.48 grams

4 0
3 years ago
Only 20 plant species, such as rice, corn,and barely, make up the main sources of food for the entire human population.
riadik2000 [5.3K]

Answer:

I believe it would be D, to enhance the survival rate.

Explanation:

7 0
3 years ago
Read 2 more answers
The raw water supply for a community contains 18 mg/L total particulate matter. It is to be treated by addition of 60 mg alum (A
s344n2d4d5 [400]

Solution :

Given :

The steady state flow = 8000 $ m^3 /d $

                                    $= 80 \times 10^5 \ I/d $

The concentration of the particulate matter = 18 mg/L

Therefore, the total quantity of a particulate matter in fluid $= 80 \times 10^5 \ I/d \times 18 \ mg/L $

$= 144 \times 10^6 \ mg/g$

$= 144 \ kg/d $

If 60 mg of alum $ [Al_2(SO_4)_3.14 H_2O] $ required for one litre of the water treatment.

So Alum required for  $ 80 \times 10^5 \ I/d $

$= 80 \times 15^5 \ I/d  \times 60 \ mg \ alum /L$

$= 480 \times 10^6 \ mg/d $

or 480 kg/d

Therefore the alum required is 480 kg/d

1 mg of the alum gives 0.234 mg alum precipitation, so 60 mg of alum will give $ = 60 \times 0.234 \text{ of alum ppt. per litre} $

      $= 14.04 $ mg of alum ppt. per litre

480 kg of alum will give = 480 x 0.234 kg/d

                                        = 112.32 kg/d ppt of alum

Daily total solid load is  $= 144 \ kg/d + 112.32 \ kg/d$

                                       = 256.32 kg/d

So, the total concentration of the suspended solid after alum addition $= 18 \ mg/L + 60 \times 0.234 $

= 32.04 mg/L

Therefore total alum requirement = 480 kg/d

b). Initial pH = 7.4

 The dissociation reaction of aluminium hydroxide as follows :

$Al(OH)_3 \rightleftharpoons Al^{3+} + 3OH^{-} $

After addition, the aluminium hydroxide pH of water will increase due to increase in $ OH^- $ ions.

Therefore, the pH of water will be acceptable range after the addition of aluminium hydroxide.

c). The reaction of $CO_2$ and water as follows :

$CO_2 (g) + H_2O (l) \rightarrow H_2CO_3$

For the atmospheric pressure :

$p_{CO_2} = 3.5 \times 10^{-4} \ atm $

And the pH is reduced into the range of 5.9 to 6.4

6 0
2 years ago
The compound trimethylamine, (CH3)3N, is a weak base when dissolved in water. Write the Kb expression for the weak base equilibr
Rina8888 [55]

<u>Answer:</u> The expression of K_b is written below.

<u>Explanation:</u>

We are given a chemical compound which is trimethylamine that acts as a weak base when dissolved in water.

It accepts a proton from the water to form trimethylammonium ion and hydroxide ion.

The chemical equation for the reaction of trimethylamine in water follows:

(CH_3)_3N+H_2O\rightleftharpoons (CH_3)_3NH^++OH^-

The expression of K_b for above equation follows:

K_b=\frac{[(CH_3)_3NH^+][OH^-]}{[(CH_3)_3N]}

Hence, the expression of K_b is written above.

5 0
3 years ago
Other questions:
  • Naming ionic compounds what are the structural units that make up ionic compounds and how are they named answers
    7·1 answer
  • The formula weight of calcium nitrate (ca(no3)2), rounded to one decimal place, is ________ amu. the formula weight of calcium n
    11·1 answer
  • Non-electrolyte = A, 10.6 grams, dissolved in solvent B, 740 grams, the boiling point of the solution is higher than the boiling
    14·1 answer
  • Henry is in the community investigating sources of chemical energy for his science experiment. Select the best examples of chemi
    5·2 answers
  • Glucose is a carbohydrate that contains carbon hydrogen and oxygen. The empirical formula of glucose is CH2O and it’s molar mass
    9·1 answer
  • Which is an example of a chemical change
    14·2 answers
  • Potassium sulfate and strontium acetate<br> Express your answer as a chemical equation
    5·1 answer
  • Propose a synthesis of phenylacetaldehyde from bromobenzene
    14·1 answer
  • How does organic matter help soil?
    14·2 answers
  • A compound has a percent composition of 15.24% sodium (molar mass = 22.99
    11·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!