Someone please help me answer this question

Estimate the air pressure at an altitude of 5km

r-ruslan [8.4K]

The answer is 100 kg

6 0

3 years ago

Is na20 a stable compound, or an unstable compound?

maria [59]

Answer:

unstable

Explanation:

3 0

2 years ago

A gaseous compound is 30.4 % N and 69.6% OF. A 5.25 g sample of the gas occupies a volume of 1.00 L and exerts a pressure of 958

Harman [31]

Answer:

The molecular formula = N2O4

Explanation:

Step 1: Data given

A gaseous compound is 30.4 % N and 69.6%

Mass of the compound = 5.25 grams

Volume of the gas = 1.00 L

Pressure of the gas = 958 mmHg = 1.26 atm

Temperature of the gas = -4 °C = 273 -4°C = 269 Kelvin

Molar mass of N = 14 g/mol

Molar mass of O = 16 g/mol

Step 2: Calculate mass of N

Mass of Nitrogen = 5.25 grams * 0.304 = 1.596 grams

Step 3: Calculate mass of O

Mass of Oxygen = 5.25 grams * 0.696 = 3.654 grams

Step 4: Calculate number of moles N

Number of moles N = Mass of N/ Molar mass of N

Moles of N = 1.596 grams / 14g/mol

Moles of N = 0.114 moles N

Step 5: Calculate moles of O

Moles O = 3.654 grams / 16 g/mol

Moles 0 = 0.2884 moles

Step 6: Calculate empirical formule

We calculate the empirical formule by dividing number of moles by the smallest number of mol

N : 0.114 / 0.114 = 1

O: 0.2284 / 0.114 = 2

Empirical formule = NO2

Step 7: Calculate number of moles of 5.25 g sample via gas law:

p*V = nRT

⇒ with p = the pressure = 1.26 atm

⇒ with v = 1.00 L

⇒ with n = the number of moles = TO BE DETERMINED

⇒ with R = the gas constant = 0.08206 L*atm/ K*mol

⇒ with T = the temperature = 269 K

number of moles n = (p*V)/(R*T)

n = (1.26*1L)/(0.08206*269)

n = 0.057 mol

Step 8: Calculate molar mass of the compound

This means 5.25 grams of the gas = 0.057 moles

So 1 mol of the compound has a molar mass of: 5.25 / 0.057 = 92.11 g/mol

Step 9: Calculate molar mass of the empirical formula NO2

N = 14 g/mol

O = 16 g/mol

NO2 = 14 + 16 + 16 = 46 g/mol

The empirical formule NO2 has a molar mass of 46 g/mol

Step 10: Calculate molecular formula

92.11 / 46 = 2

This means the empirical formula should be multiplied by 2

2*(NO2) = N2O4

The molecular formula = N2O4

8 0

2 years ago

Describe the main difference between the Bohr model and the electron cloud model of the atom

Leno4ka [110]

Answer:

The main difference between the two models is the position of the electron in the atom.

Explanation:

Bohr model: The electrons are moved around the nucleus in circular definite paths (orbitals or shells). Also, he could not find or detect the exact position of electron.

Electron cloud model: It is supposed by Erwin Schrodinger. He showed that the emission spectra of the atom is the way to detect the probability of electron position.

4 0

2 years ago

Read 2 more answers

25. How many ml of a .0023M strontium hydroxide solution are needed to completely react 15.0 mL of 0.012M hydrochloric acid?

Mariana [72]

Answer: There are 78.26 mL of a 0.0023M strontium hydroxide solution are needed to completely react 15.0 mL of 0.012M hydrochloric acid.

Explanation:

Given: $M_{1}$ = 0.0023 M, $V_{1}$ = ?

$V_{2}$ = 15.0 mL, $M_{2}$ = 0.012 M

Formula used to calculate volume of strontium hydroxide solution is as follows.

$M_{1}V_{1} = M_{2}V_{2}$

Substitute the values into above formula as follows.

$M_{1}V_{1} = M_{2}V_{2}\\0.0023 M \times V_{1} = 0.012 M \times 15.0 mL\\V_{1} = 78.26 mL$

Thus, we can conclude that there are 78.26 mL of a 0.0023M strontium hydroxide solution are needed to completely react 15.0 mL of 0.012M hydrochloric acid.

8 0

3 years ago