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
nignag [31]
2 years ago
14

Bài 1. Có 30g dung dịch NaCl 20%. Tính nồng độ % dung dịch thu được khi

Chemistry
1 answer:
AlladinOne [14]2 years ago
6 0

Answer:

Bài 1. Có 30g dung dịch NaCl 20%. Tính nồng độ % dung dịch thu được khi

a. Pha thêm 20g H2O

b. Cô đặc dung dịch để chỉ còn 25g.

You might be interested in
How many neutrons are in the nucleus of an atom that has an atomic mass of 36 and an atomic number of 25?
elixir [45]

Answer:

Neutrons = 11

Explanation:

To get the number of neurons an element has you have to subtract the number of protons from the atomic mass of that element.

The number of protons is equal to the atomic number of that element.

Atomic number = Number of Protons

So the number of protons is 25

Neutrons = Atomic mass - Number of Protons

Neutrons = 36 - 25

Neutrons = 11

6 0
3 years ago
Read 2 more answers
Someone help me pls will make you as brain
jonny [76]

Answer:

i, ii, and iii

Explanation:

3 0
2 years ago
Read 2 more answers
Which statement correctly describes the relationship between reactant and yield?
wlad13 [49]

Answer:

The theoretical yield is calculated from the amount of the limiting reactant present.

3 0
3 years ago
Boron carbonate decomposes into boron oxide and carbon dioxide. How many moles of CO2
Paul [167]
<h3>Answer:</h3>

15 moles

<h3>Explanation:</h3>

The decomposition of boron carbonate is given by the equation;

B₂(CO₃)₃(s) → B₂O₃(s) + 3CO₂(g)

Moles of boron carbonate decomposed is 5.0 mol

To find the moles of CO₂ produced we are going to use the mole ratio.

Mole ratio of B₂(CO₃)₃ to CO₂ is 1 : 3

Therefore;

Moles of CO₂ = Moles of B₂(CO₃)₃ × 3

                      = 15 mol

Therefore, 15 moles of CO₂ will be produced

   

4 0
3 years ago
In the reaction 2Mg (s) + O2 (g) + 2H2O (l) → 2Mg2+ (aq) + 4OH– (aq), which substance is reduced?
Bogdan [553]

F. <em>None of the above </em>

<em>No O atoms are present</em> as reacting substances, only O_2 and H_2O molecules.

O_2 + 2H_2O + 2e^(-) → 4OH^(-)

We must use <em>oxidation numbers</em> to decide whether oxygen or water is the substance reduced.

The oxidation number of O changes from 0 in O_2 to -2 in OH^(-).

A decrease in oxidation number is <em>reduction</em>, so O_2 is the substance  reduced.

The oxidation number of O is -2 in both H_2O and OH^(-), so water is <em>neither oxidized nor reduced</em>.

6 0
3 years ago
Other questions:
  • Pls answerrrrrrrrrrrrrrrrrrrrrrrrrrrrr​
    14·1 answer
  • Sam lives in the city of Springdale and is interested in how the climate in his city compares to the climate in Ecuador. Which o
    13·1 answer
  • How many liters of gaseous hydrogen bromide at 58°C and 0.891 atm will a chemist need if she wishes to prepare 3.50 L of 1.20 M
    6·2 answers
  • A tire at 21ÁC has a pressure of 0.82 atm. Its temperature decreases to _3.5ÁC. If there is no volume change in the tire, what i
    5·1 answer
  • Megan left her bicycle outside on the patio while she went on vacation for several weeks. When she returned, Megan discovered a
    12·2 answers
  • A rocket will rotate about a single point called the _?
    12·2 answers
  • What determines the traits of offspring?A.Food sources that have been genetically engineered B.Literary metaphors and exciting c
    6·1 answer
  • When an acid and base react, salt and water is formed.<br><br> True<br><br> False
    10·1 answer
  • Which of the following conclusions might a scientist make when fossils of two different species of very similar organisms are fo
    9·1 answer
  • Consider an atom having four distinct energy levels. If an electron is able to make transitions between any two levels, how many
    6·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!