In the periodic table, which elements had complete outer shells? Also include name and symbol

Which of the following gases will escape through a hole in a balloon at the highest rate? Kr NO Ar N2O

densk [106]

Answer:

NO.

Explanation:

The rate of diffusion of gases is inversely proportional to the square root of its density as explained by Graham's law of diffusion i.e

Rate (R) & 1/√(density (d))

R & 1/√d

But the density of a gas is proportional to the molar mass (M) of the gas.

Thus, the above equation can written as:

R & 1/√d

R & 1/√M

This implies that rate is inversely proportional to the molar mass of a gas i.e the lighter the gas, the faster the rate and the heavier the gas, the slower the rate of diffusion.

Now, to obtain the answer to the question, let us determine the molar mass of each gas.

This is illustrated below:

Molar mass of Kr = 84 g/mol

Molar mass of NO = 14 + 16 = 30 g/mol

Molar mass of Ar = 40 g/mol

Molar mass of N2O = (14x2) + 16 = 44 g/mol

Summary

Gas >>>>>>> Molar mass

Kr >>>>>>>>> 84 g/mol

NO >>>>>>>> 30 g/mol

Ar >>>>>>>>> 40 g/mol

N2O >>>>>>> 44 g/mol

From the above table, we can see the lightest gas is NO.

Therefore, NO will escape through the hole in the balloon at the highest rate.

4 0

3 years ago

One reaction that produces hydrogen gas can be represented by the unbalanced chemical equation Mg+HCl=MgCl2+H2. What mass of HCl

Delicious77 [7]

I the HCI is the mass of the equation but not always answer is Mg+HC H20

3 0

3 years ago

How many chloride ions are in a 220 grams of calcium chloride?

steposvetlana [31]

Answer: Hello, There! Your Answer is Below

2.4 x 1024 ions

Explanation:

220 g of CaCl₂ = X moles

Solving for X,

X = (220 g × 1 mol) ÷ 110.98 g

X = 1.98 moles

As,

1 mole contained = 1.20 × 10²⁴ Cl⁻ Ions

Then,

1.98 mole will contain = X Cl⁻ Ions

Solving for X,

X = (1.98 mol × 1.20 × 10²⁴ Ions) ÷ 1mol

X = 2.38 × 10²⁴ Cl⁻ Ions

Hope this Helps!

Have a great DAy!

`August~

3 0

2 years ago

You decided to prepare a phosphate buffer from solid sodium dihydrogen phosphate (NaH2PO4) and disodium hydrogen phosphate (Na2H

KIM [24]

Answer:

For disodium hydrogen phosphate:

5.32g Na2HPO4

For sodium dihydrogen phosphate:

7.65g Na2HPO4

Explanation:

First, you have to put all the data from the problem that you going to use:

-NaH2PO4 (weak acid)

-Na2HPO4 (a weak base)

-Volume = 1L

-Buffer pH = 7.00

-Concentration of [NaH2PO4 + Na2HPO4] = 0.100 M

What we need to find the pKa of the weak acid, in this case NaH2PO4, for that you need to find the Ka (acid constant) of NaH2PO4, and for this we use the pKa of the phosphoric acid as follow:

H3PO4 = H2PO4 + H+ pKa1 = 2.14

H2PO4 = HPO4 + H+ pKa2 = 6.86

HPO4 = PO4 + H+ pKa3 = 12.4

So, for the preparation of buffer, you need to use the pKa that is near to the value of the pH that you want, so the choice will be:

pKa2= 6.86

Now we going to use the Henderson Hasselbalch equation for the pH of a buffer solution:

pH = pKa2 + log [(NaH2PO4)/(Na2HPO4)]

The solution of the problem is attached to this answer.

Download odt

7 0

3 years ago

Calculate AH°rxn from AH°7 values (use table in textbook appendix) a) Cl2 (g) + 2 Na (s) -› 2 NaCl (s) EITHER -411.1kJ/mol b) 2

MrMuchimi

To find AH°rxn, we use the following equation:

What we're going to do is to sum the enthalpy of the products and then substract with the enthalpy of the reactives:

As you can see, we need to multiply by the coefficients of the reaction.

Now, just replace the values of the table:

So the answer is -822.2kJ/mol.

For b:

Now, just replace the values of the table:

The answer for b is -1036kJ/mol.

4 0

1 year ago