Please please please help please

Answer:

Both molarity and formality express concentration as moles of solute per liter of solution. Formality is a substance's total concentration in solution without regard to its specific chemical form. ... The formality of a solution is defined as the number of formula mass of any solute dissolved in 1 litre of solution.

Answer: 1.95 g of oxygen is present.

Explanation:

According to Dalton's law, the total pressure is the sum of individual pressures.

[tex]p_{total}=p_{methane}+p_{oxygen}[/tex]

Given : [tex]p_{total}[/tex] =total pressure of gases = 727 mm Hg

[tex]p_{methane}[/tex] = partial pressure of methane = 571 mm Hg

[tex]p_{oxygen}[/tex] = partial pressure of oxygen = ?

[tex]727=571+p_{oxygen}[/tex]  

[tex]p_{oxygen}=156mmHg[/tex]

Also [tex]p_{oxygen}=x_{oxygen}\times p_{total}[/tex]

Given : 3.62 g of methane is present

moles of methane = [tex]\frac{\text{Given mass}}{\text {Molar mass}}=\frac{3.62g}{16g/mol}=0.226moles[/tex]

[tex]x_{oxygen}[/tex] = mole fraction of oxygen  

=[tex]\frac{\text {moles of oxygen}}{\text {total moles}}=\frac{y}{y+0.226}[/tex]

[tex]156=\frac{y}{y+0.226}\times 727[/tex]

[tex]y=0.061[/tex]

mass of oxygen = [tex]moles\times {\text {Molar mass}}=0.061\times 32=1.95g[/tex]

Thus 1.95 g of oxygen is present.

Answer:

Milk's heavy

Explanation:

Answer:

This question appear incomplete

Explanation:

This question appear incomplete. However, let's answer the resulting questions. Firstly, let's define mass number since each of the "problems" refers to mass number. Mass number is the total number of protons and neutrons in the nucleus of an atom. It should also be noted that number of protons in any given neutral atom is the same with the number of electrons of such an atom.

1) Make a He atom with a mass of 4. How many protons did you put in the nucleus?

Answer: Helium (He) atom (having a mass number of 4) has an atomic number of 2. Atomic number is the number of protons and thus 2 protons would be in the nucleus of the Helium atom.

2) Make a Li atom with a mass number of 7. How many electrons did you place in the outermost orbital  (ring)?

Answer: Lithium (Li) atom (having a mass number of 7) has an atomic number of 3. Remember that atomic number (number of protons) equals number of electrons in a neutral atom. Thus, lithium atom would have 3 electrons; 2 electrons in it's first shell and 1 electron in it's outermost shell

3) Make a N atom with a mass number of 14. How many neutrons are in the nucleus?

Answer: Nitrogen (N) atom (with a mass number of 14) has an atomic number of 7. Since atomic number is the number of protons and mass number is the number of protons + neutrons. Then, number of neutrons would equal mass number minus atomic number:

number of neutrons = 14 - 7

number of neutrons = 7 neutrons

4) Make a B atom with a mass number of 11. How many electrons did you put in the second orbital (ring)?

Answer: An atom (Boron) with mass number of 11 has an atomic number of 5. Since atomic number eventually equals number of electrons, then Boron has 5 electrons; 2 electrons in it's first shell and 3 electrons in it's second orbital/ring.

Answer:

2 protons in the He nucleus,

1 electron in the outermost,

7 neutrons in the nucleus

3 electrons in the  2nd orbital ring

Explanation:

I just did it on E2020

Answer:

water

Explanation:

because the others are in compounds and can not be considered as  products lonely.