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
lubasha [3.4K]
2 years ago
7

25g of magnesium chloride (MgCl2) was dissolved in 250 ml distilled water at 25oC. The density of water was 0.9975g/cm3 . Calcul

ate the concentration in molality.
Chemistry
1 answer:
andriy [413]2 years ago
6 0

Answer:

[MgCl₂] = 1.05 m

Explanation:

Molality is a type of concentration that indicates the moles of solute in 1000g of solvent.

m = mol/kg.

Our solute is MgCl₂. We convert mass to moles:

25 g . 1mol / 95.21 g = 0.262 moles.

Our solvent is water → 250 mL of H₂O

We use density to determine the mass: density = m / V

Density . V = m → 0.9975 g/mL . 250 mL = 249.3 g

We convert from g to kg = 249.3 g . 1kg/1000g = 0.2493kg

molality → 0.262 mol /0.2493kg = 1.05

You might be interested in
What are two ways that scientists u measure temperature
anygoal [31]

Using the same anchor points, he determined the freezing temperature for water to be 0 degree and the boiling temperature 100 degrees. The Celsius scale is known as a Universal System Unit. It is used throughout science and in most countries.


8 0
3 years ago
How can you use the Periodic Table of Elements to help you find information about specific elements? PLZZZ HELP MEEEEEE!!!!
elena-14-01-66 [18.8K]

Answer:

Yuh imma help-........

6 0
2 years ago
A mixture in which particles are not evenly distributed and particles keep their unique properties.
lina2011 [118]
<h2>Answer : Option D) Heterogeneous mixture</h2><h3>Explanation : </h3>

A mixture in which particles are not evenly distributed and particles keep their unique properties are called as heterogeneous mixture.

Usually, in heterogeneous mixture the substances are not evenly distributed and they can be easily separated through any physical methods.  Also the components retains their original/unique properties in the mixture. It usually contains various particles from different substances that are not uniformly distributed throughout the mixture.

4 0
2 years ago
Read 2 more answers
In an experiment, hydrochloric acid reacted with different volumes of sodium thiosulfate in water. A yellow precipitate was form
erastovalidia [21]

Answer:

The time taken for the cross mark to disappear decreases steadily down the column.

Explanation:

Now if we look at the data provided, we will discover that the volume of the HCl was held constant while the volume of the thiosulphate was increased steadily and the volume of water decreased steadily.

Recall that a system is more concentrated when it contains less volume of water and more volume of reactants. Hence as the volume of water in the system is being reduced, the concentration of reactants is increased.

It has been established that an increase in the concentration of reactants lead to an increase in the rate of reaction. The disappearance of the cross shows the completion of the reaction between HCl and thiosulphate. The faster or slower the cross disappears, the faster or slower the rate of reaction.

Since increase in concentration of reactants increases the rate of reaction, it is observed that as the volume of the thiosulphate increases (reactant concentration increases) the cross disappears faster (rate of reactant increases). Hence as the volume of thiosulphate increases, it takes a shorter time for the cross to disappear. This implies that the time column in the table (refer to the question) will decrease steadily as the volume of thiosulphate increases.

5 0
3 years ago
1 kilocalorie is equal to<br> calories.<br><br> 1000
rusak2 [61]

Answer:

it is equal to 1000 gram calories

8 0
2 years ago
Read 2 more answers
Other questions:
  • Look at the questions below and decide which is declarative.
    14·1 answer
  • 1. The density of solid Cu is 8.96g/cm3 . How many atoms are present per cubic centimeter(cm3) of Cu ?
    12·1 answer
  • What is the pressure of a sample of gas at a volume of .335 L if it occupies 1700 mL at
    14·1 answer
  • Which of the following statements is not true regarding molecular orbital theory? O Bonding molecular orbitals have lower energy
    14·1 answer
  • A chemical reaction was used to produce 2.54 moles of copper(II) bicarbonate, Cu(HCO3)2. What mass of copper(II) bicarbonate was
    10·1 answer
  • g Which of the following solutes in aqueous solution would be expected to exhibit the smallest freezing-point lowering (assuming
    12·1 answer
  • Depression what are the effects to the brain
    11·1 answer
  • Which metal gets coated during electroplating? A. The metal with electrons flowing from it
    14·1 answer
  • Formula for Ni2+ and NO3
    10·1 answer
  • What has the highest ionization energy Na, Mg, Al
    8·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!