All categories

3 years ago

C-12, c-13, and c-14 have the same number of protons but different numbers of neutrons so they are

Chemistry

1 answer:

laiz [17]3 years ago

6 0

Atoms with the same number of protons, but different numbers of neutrons are isotopes of the same element.

You might be interested in

Which of the following phase changes describes what is

stich3 [128]

Answer:

I think the answer is boiling

8 0

3 years ago

A mouse is placed in a sealed chamber with air at 769.0 torr. This chamber is equipped with enough solid KOH to absorb any CO2 a

svlad2 [7]

<u>Answer:</u> The amount of oxygen gas consumed by mouse is 0.202 grams.

<u>Explanation:</u>

We are given:

Initial pressure of air = 769.0 torr

Final pressure of air = 717.1 torr

Pressure of oxygen = Pressure decreased = Initial pressure - Final pressure = (769.0 - 717.1) torr = 51.9 torr

To calculate the amount of oxygen gas consumed, we use the equation given by ideal gas which follows:

$PV=nRT$

where,

P = pressure of the gas = 51.9 torr

V = Volume of the gas = 2.20 L

T = Temperature of the gas = 292 K

R = Gas constant = $62.364\text{ L. Torr }mol^{-1}K^{-1}$

n = number of moles of oxygen gas = ?

Putting values in above equation, we get:

$51.9torr\times 2.20L=n\times 62.364\text{ L. Torr }mol^{-1}K^{-1}\times 292K\\\\n=\frac{51.9\times 2.20}{62.364\times 292}=0.0063mol$

To calculate the mass from given number of moles, we use the equation:

$\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}$

Moles of oxygen gas = 0.0063 moles

Molar mass of oxygen gas = 32 g/mol

Putting values in above equation, we get:

$0.0063mol=\frac{\text{Mass of oxygen gas}}{32g/mol}\\\\\text{Mass of oxygen gas}=(0.0063mol\times 32g/mol)=0.202g$

Hence, the amount of oxygen gas consumed by mouse is 0.202 grams.

5 0

3 years ago

I need part 1 and 2 please , just separate answers

Vladimir79 [104]

First, we have to remember the molarity formula:

$M=\text{ }\frac{moles\text{ of solute}}{L\text{ solution}}$

Part 1:

In this case, our solute is sodium nitrate (NaNO3), and we have the mass dissolved in water, then we have to convert grams to moles. For that, we need the molecular weight:

$M.W_{NaNO_3}=\text{ 23+14+16*3= 85 g/mol}$

Then, we calculate the moles present in the solution:

$3.976\text{ g NaNO}_3\text{ * }\frac{1\text{ mol}}{85\text{ g}}=\text{ 0.04678 mol NaNO}_3$

Now, we have the necessary data to calculate the molarity (with the solution volume of 200 mL):

$M=\frac{0.04678\text{ mol}}{200\text{ mL*}\frac{1\text{ L}}{1000\text{ mL}}}=\text{ 0.2339 M}$

The molarity of this solution equals 0.2339 M.

Part 2:

In this case, we have the same amount (in moles and mass) of sodium nitrate, but a different volume of solution, then we only have to change it:

$M=\text{ }\frac{0.04678\text{ mol}}{275\text{ mL *}\frac{1\text{ L}}{1000\text{ mL}}}=\text{ 0.1701 M}$

So, the molarity of this solution is 0.1701 M.

5 0

1 year ago

(worth 10pts!!!!!!) What did Dmitri Mendeleev contribute to science? A. He arranged the first periodic table. B. He developed th

vesna_86 [32]

Answer:

A. He arranged the first periodic table.

Explanation:

3 0

3 years ago

Read 2 more answers

Describe the structure of an Atom (HELP!)

Marat540 [252]

Answer:

The answer is A.

Explanation:

Neutrons and protons are located in the dense middle of the atom called the nucleus, and electrons are located on the electron cloud located outside of the nucleus.

4 0

3 years ago