All categories

4 years ago

What is the molarity of a solution that is made by adding 57.3 g of MgO to 500.0 mL of solution?

Chemistry

1 answer:

kifflom [539]4 years ago

0 0

Answer:

2.843 M

Explanation:

Molarity = moles / volume

Milliliters to liters:

500 mL = .500 L

Grams to moles:

MgO molar mass = 16.00 + 24.31 = 40.31 g/mol

57.3 g x 1 mol / 40.31 g = 1.421 mol

Molarity:

1.421 mol / .500 L = 2.843 M

You might be interested in

What happens when you put on deodorant? does it absorb heat and give off thermal energy

Lunna [17]

It absorbs heat and give off thermal energy just saying i think its right

3 0

4 years ago

tino4ka555 [31]

Answer : The correct option is, electron.

Explanation :

As we know that,

An atom is the smallest unit of a matter that consist of three subatomic particles which are electrons, protons and neutrons.

The protons and the neutrons are located inside the nucleus or the center of the nucleus where the mass of the an atom is concentrated.

The electrons are located around the nucleus.

The protons are positively charged, the electrons are negatively charged and the neutrons are neutral that means it has no charge.

According to the question, the electron subatomic particle found revolving around the nucleus.

Hence, the correct option is electron.

5 0

3 years ago

Convert 863,000,000,000,000 to scientific notation use four significant figures

serg [7]

8.630 x 10^14

U can hav an infinite amount of zeros if they are trailing zeros. We all call them ambiguous.

5 0

3 years ago

28. How many formula units are found in 0.250 moles of potassium nitrate?

Soloha48 [4]

Answer:

$\boxed {\boxed {\sf B. \ 1.5 *10^{23} \ formula \ units}}$

Explanation:

1 mole of any substance contains the same number of particles. The particles can vary (atoms, molecules, formula units), but there are always 6.022*10²³ particles. In this case, the particles are formula units of potassium nitrate or KNO₃.

Let's create a ratio.

$\frac {6.022*10^{23} \ formula \ units \ KNO_3}{1 \ mol \ KNO_3}$

Since we are trying to find the formula units in 0.250 moles, we multiply by that number.

$0.250 \ mol \ KNO_3 *\frac {6.022*10^{23} \ formula \ units \ KNO_3}{1 \ mol \ KNO_3}$

The units of moles of potassium nitrate cancel.

$0.250 *\frac {6.022*10^{23} \ formula \ units \ KNO_3}{1 }$

The denominator of 1 can be ignored, so we can make a simple multiplication problem.

$0.250 *{6.022*10^{23} \ formula \ units \ KNO_3}$

$1.5055 * 10^{23} \ formula \ units \ KNO_3$

If we round to the nearest tenth, the 0 in the hundredth place tells us to leave the 5 in the tenth place.

$1.5 *10^{23} \ formula \ units \ KNO_3$

0.250 moles of potassium nitrate is approximately equal to 1.5*10²³ formula units of potassium nitrate and choice B is correct.

7 0

3 years ago

A gas has a pressure of 3.16 atm at STP. I have decided to transfer it to a container that is 3 times larger than the original v

Oliga [24]

Answer:

The new pressure is 1.0533 atm

Explanation:

According to Boyle's Law : The Pressure of fixed amount of gas is inversely proportional to Volume at constant temperature.

PV = Constant

P1V1 = P2V2

$P_{1}V_{1}=P_{2}V_{2}$ .....(1)

P1 = 3.16 atm

Accprding to question ,

V1 = V

V2 = 3 V

Insert the value of V1 , V2 and P1 in the equation(1)

$P_{1}V_{1}=P_{2}V_{2}$

$3.16\times V=P_{2}\times 3V$

V and V cancel each other

$3.16=P_{2}\times 3$

$P_{2}=\frac{3.16}{3}$

$P_{2}=1.05atm$

5 0

3 years ago