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
Serga [27]
4 years ago
5

Determine the molality of an aqueous solution that is 15.5 percent urea by mass.

Chemistry
1 answer:
DaniilM [7]4 years ago
3 0

15.5% by mass is equivalent 15.5 g urea in 100 g solution or 155 g urea in 1 kg solution. <span>

<span>we know that molality = moles solute / kg solvent

<span>moles solute = 155 g / 60 g/mol = 2.58 moles urea

</span></span></span>

Since there are 155 g urea in 1000g solution, hence the solvent is 845 g or 0.845 kg

So:<span>
<span>molality = 2.58 / 0.845 = 3.06 m</span></span>

You might be interested in
What is the latitude and longitude of the copper mine in Wisconsin (WI)?
rusak2 [61]
The answer is  A. 45*N. and 91*W.
7 0
3 years ago
As a maritime air mass moves across land, what happens to the air mass?
jasenka [17]

Answer:

the air mass will become colder

Explanation:

A maritime tropical air mass is moist and warm, while a continental polar air mass is dry and cold. ... When an air mass moves to a new region, it carries along its characteristic moisture and temperature. As the air moves over Earth's surface, the characteristics of the surface begin to change the air mass.

6 0
3 years ago
A scientist claims to have discovered an element with 30 protons in its nucleus. He determines it has 60 electrons. Why is his i
UNO [17]

The number of electrons in an atom of an element being always the same

as the number of protons in its nucleus is False.

<h3>What is an Electron?</h3>

This is a sub-atomic particle which is negatively charged and is usually

involved in chemical reactions.

Electropositive elements donates electrons while electronegative

elements accepts electrons during chemical reactions which is why the

number of proton and electron aren't always the same.

Read more about Electrons here brainly.com/question/900457

4 0
2 years ago
Read 2 more answers
What is the formula for the conjugate base formed by the following acid<br> HCN
meriva

Answer:

HCN - Hydrogen cyanide The conjugate acid of CN- is HCN. HCN stands for hydrogen cyanide. The conjugate acids are a combination of a strong acid and a low base.

5 0
3 years ago
To test paint quality, scientists designed an experiment where the paint was exposed to temperatures ranging from 260 degrees Ce
pishuonlain [190]

Answer:

The independent variable is the temperature to which the paint and materials are exposed

The dependent variable is the presence of peeling and cracking of the paint

The constant rates are the paint and material used for each trial

Explanation:

The treatment the to which the paint is subjected = Temperatures from 260 °C  to 650 °C

The method of determining the paint quality = By peeling and cracking

The types of paint and materials used = The same paint and material

The independent variable is the variable suspected as the cause of the effect being studied. It is the variable introduced as a treatment

In the question, given that the paint is subjected to different temperatures from between 260°C to 650 °C, the temperature changes introduced is the independent variable

Therefore;

The independent variable = The temperature to which the paint and materials are exposed to

The dependent variable is the effect variable. It is the variable of the property being investigated and it is also the variable that is measured in the investigation

In the question, given that the after heating the paint and material, the scientist check for peeling and cracking, the dependent variable is the occurrence of cracking and peeling at a given temperature

Therefore;

The dependent variable = The presence of peeling and cracking of the paint

The constant rate(s) are variables which are kept constant during the investigation, under the different treatments

The constant rate(s) in the tests are the paint and material, which were kept the same for each trial to reduce the effect of underlying factors that may impact on the result and obscure the relationship between the dependent and independent variables

Therefore;

The constant rate are the paint and material used for each trial

8 0
3 years ago
Other questions:
  • Draw the Alkane Diagram for: <br> 1,3-dibutyl - 2,3,4 - trimethyl cyclooctane
    14·1 answer
  • What is the correct answer in scientific notation? 1.2x104 x 1.2x108 =
    13·1 answer
  • What is octane classified as
    6·2 answers
  • In an aqueous solution, the solute is the part of the solution that is being dissolved in water.
    15·2 answers
  • 73.5 grams C, 4.20 grams H, and 72.3 grams Cl. What is the percent composition of each element in this compound?
    12·1 answer
  • If you weigh 240 pounds on Earth, what is your weight on the moon?
    5·2 answers
  • Which statement describes acids
    15·1 answer
  • How can an experiment support or fail support a hypothesis
    12·1 answer
  • Ive been on this for 30 min and I’m kinda struggling so if anyone can help me that wiped be Appreciated
    6·2 answers
  • Is dimensional analysis the same thing as unit conversions?
    10·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!