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
juin [17]
3 years ago
13

Calculate the concentration in % (m/m) of a solution containing 30.0g of mgcl2 dissolved in 270.0g of h20

Chemistry
1 answer:
qaws [65]3 years ago
4 0
As the question tells you, you need to use the formula

% mass= mass of solute/ mass of solution x 100

mass solute= 30.0 g
mass of solution= 30.0 + 270.0= 300.0 g

% mass= 30.0/ 300.0 x 100= 10%

answer is B
You might be interested in
How many moles are equal to 1.3 x 1024 atoms of aluminum?
marshall27 [118]

Answer:

<h3>The answer is 2.16 moles</h3>

Explanation:

To find the number of moles in a substance given it's number of entities we use the formula

n =  \frac{N}{L}  \\

where n is the number of moles

N is the number of entities

L is the Avogadro's constant which is

6.02 × 10²³ entities

From the question we have

n =  \frac{1.3 \times  {10}^{24} }{6.02 \times  {10}^{23} }  \\  = 2.159468...

We have the final answer as

<h3>2.16 moles</h3>

Hope this helps you

8 0
3 years ago
If 2 CH3OH + 3 O2 -&gt; 2CO2 + 4 H2O was carried out in the laboratory and 219 g of water was produced, what would the percent y
ANEK [815]

Answer:

Percent yield = 84.5 %

Explanation:

Given data:

Mass of methanol = 229 g

Actual yield of water = 219 g

Percent yield of water = ?

Solution:

Chemical equation:

2CH₃OH + 3O₂  →  2CO₂  + 4H₂O

Number of moles of methanol:

Number of moles = mass/ molar mass

Number of moles = 229 g/ 32 g/mol

Number of moles = 7.2 mol

Now we will compare the moles of water with methanol.

                        CH₃OH         :            H₂O

                            2               :               4

                           7.2             :           4/2×7.2 = 14.4 mol

Mass of water:

Mass = number of moles × molae mass

Mass = 14.4 mol × 18 g/mol

Mass = 259.2 g

Percent yield:

Percent yield = actual yield / theoretical yield × 100

Percent yield = 219 g / 259.2 g × 100

Percent yield = 84.5 %

7 0
3 years ago
Complete and balance the following acid-base equations:
Alchen [17]

Answer:

a) HClO_4 (aq) + LiOH \rightarrow LiClO_4 + H_2O

b) H_2SO_4(aq) + 2NaOH(aq) \rightarrow Na_2SO_4 (aq) + 2H_2O (l)

c) Ba(OH)2 + 2HF\rightarrow BaF_2 + 2H_2O

Explanation:

a)

when HClO_4 is added to LiOH, lithium chlorate and water is formed.

HClO_4 (aq) + LiOH \rightarrow LiClO_4 + H_2O

Balancing of above reaction,

It can be seen that all the atoms in both the sides are balanced. so it is a balanced reaction.

(b) When aqueous H_2SO_4 is added to NaOH, Na_2SO_4 and H_2O is formed. It is a neutrilization reaction.

H_2SO_4(aq) + NaOH(aq) \rightarrow Na_2SO_4 (aq) + H_2O (l)

Balancing of above reaction,

First balance all the atoms except O and H

S atom is already balanced in either side

No. of Na atom in left hand side = 1

No. of Na atom in right hand side = 2

So multiply NaOH by 2, now the reaction becomes:

H_2SO_4(aq) + 2NaOH(aq) \rightarrow Na_2SO_4 (aq) + H_2O (l)

No. of O atoms in left hand side = 6

No. of O atoms in right hand side = 5

So multiply H2O by 2, now the reaction becomes:

H_2SO_4(aq) + 2NaOH(aq) \rightarrow Na_2SO_4 (aq) + 2H_2O (l)

Now, it can been seen that all the atoms are balanced.

c) When Ba(OH)2 reacts with HF, baroum fluoride and water is formed.

Ba(OH)2 + HF\rightarrow BaF_2 + H_2O

Balancing of above reaction,

Barium atoms are already balanced on either side.

No. of F atoms on left hand side = 1

No. of F atoms on right hand side = 2

So, multiply HF by 2, now reaction becomes

Ba(OH)2 + 2HF\rightarrow BaF_2 + H_2O

In order to balance H and O on either side, multiply H2O by 2.

Ba(OH)2 + 2HF\rightarrow BaF_2 + 2H_2O

7 0
3 years ago
PLEASE HELP
DENIUS [597]

I believe that it is B

3 0
3 years ago
1. What is the first element on the periodic table?
Elena L [17]
Hydrogen as it has only 1 proton and therefore only an atomic mass of 1...
7 0
3 years ago
Read 2 more answers
Other questions:
  • What are the chemical components of a dna molecule??
    11·2 answers
  • In 1887, Albert A. Michelson and Edward W. Morley conducted an experiment to measure the speed at which the Earth moves through
    13·2 answers
  • When chlorine and magnesium react chemically, how many chlorine atoms will combine with one magnesium atom?
    5·1 answer
  • How many sodium ions are present in 325 ml of 0.850 m na2so4?
    14·1 answer
  • Compare blue and violet light. which one has the highest energy?<br> Longest wavelength?
    13·1 answer
  • Please help me I would really appreciate it
    13·1 answer
  • Which of the following is the best definition of an atom?
    8·2 answers
  • What my happen in the ecosystem of the fox was removed
    10·1 answer
  • Imagine That you're living in Miami Florida And your family have decided That it's time to move it to the new home. Which of the
    7·1 answer
  • Create a time that marks important events during the Precambrian Supereon.
    6·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!