Assuming 80 mg of vitamin c present 29.57 ml if oj how many milliliters of 0

A solution is made by mixing equal masses of methanol, CH 4 O , and ethanol, C 2 H 6 O . Determine the mole fraction of each com

Fynjy0 [20]

Answer:

Mole fraction of $CH_4O$ = 0.58

Mole fraction of $C_2H_6O$ = 0.42

Explanation:

Let the mass of $CH_4O$ and $C_2H_6O$ = x g

Molar mass of $CH_4O$ = 33.035 g/mol

The formula for the calculation of moles is shown below:

$moles = \frac{Mass\ taken}{Molar\ mass}$

Thus,

$Moles_{CH_4O}= \frac{x\ g}{33.035\ g/mol}$

$Moles_{CH_4O}=\frac{x}{33.035}\ mol$

Molar mass of $C_2H_6O$ = 46.07 g/mol

Thus,

$Moles= \frac{x\ g}{46.07\ g/mol}$

$Moles_{C_2H_6O}=\frac{x}{46.07}\ mol$

So, according to definition of mole fraction:

$Mole\ fraction\ of\ CH_4O=\frac {n_{CH_4O}}{n_{CH_4O}+n_{C_2H_6O}}$

$Mole\ fraction\ of\ CH_4O=\frac{\frac{x}{33.035}}{\frac{x}{33.035}+\frac{x}{46.07}}=0.58$

Mole fraction of $C_2H_6O$ = 1 - 0.58 = 0.42

6 0

3 years ago

A. how do you determine the charge of an element?

NemiM [27]

Answer:

Explanation:

A. The charge on an element is determined by the differences between the number of protons and electrons in an atom.

An atom will have no charges if the number of protons and electrons are the same.

When an atom loses or gains electrons, the number of electrons will either decrease or increase
if the number of electrons is more than the number of protons, the excess electrons is the charge on the atom. And this makes the atom become a negatively charged ion.
if the number of electrons is lesser than the number of protons, the deficient electrons makes the atom a positively charged ion. The number of electrons by which the atom is deficient makes the atom a positively charged ion.

Charge = number of protons - number of electrons

B. Electrons form the charges they do because with the charge, they become stable like the noble gases.

The desire of every atom is to have stable electronic configuration like those of the noble gases.

A potassium atom with a configuration 2 8 8 1 will prefer to lose an electron to become an Argon atom making the ion stable.

3 0

2 years ago

A container holds 6.4 moles of gas. Hydrogen gas makes up 25% of the total moles in the container. If the total pressure is 1.24

Degger [83]

The partial pressure of hydrogen is 0.31 atm

calculation

find the number of hydrogen moles the container, that is

25/100 x 6.4 =1.6 moles of hydrogen

find the partial pressure for hydrogen in 1.6 moles

that is 6.4 moles= 1.24 atm
1.6 moles= ?

by cross multiplication

1.6moles x1.24 atm/ 6.4 moles= 0.31 atm

6 0

3 years ago

A 10.0-g sample of sodium chloride was placed in 10.0 g of water. If 3.85 g of Cl2 was obtained, what was the percent yield of C

suter [353]

Answer:

63.53% yield

Explanation:

The balanced equation for this reaction is 2NaCl + H2O -> 2NaOH +Cl2

First we must find the limiting reactant

From NaCl we can only produce 6.06 grams of Cl2 in <u>theory</u>

From H20 we can only produce 38.995 grams in theory

so we know NaCl is the limiting

% yield is (Actual/Theoretical) x100 so

(3.85/6.06)x100= 63.53% yield

7 0

2 years ago

Please help

lisabon 2012 [21]

Answer:

There are 2 hydrogen atoms, one magnesium atom, and 5 atoms in total.

Explanation:

We are given a compound in formula form. To make things easier to understand, we can first convert this to the name of the compound.

When a compound contains one or more elements in parentheses, these are usually a <u>polyatomic ion</u>.
Polyatomic ions are ions made up of two or more elements with a positive or negative charge over the entire ion. Commons examples of these NH₄⁺ (ammonia) and HCO₃⁻ (bicarbonate).
You can combine metals with polyatomic ions to create commonly known compounds, such as baking soda. The chemical name for baking soda is sodium bicarbonate, so we can combine Na (sodium) with HCO₃⁻ (bicarbonate) and create sodium bicarbonate: NaHCO₃.

This compound is one magnesium atom bonded to two hydroxide ions.

Hydroxide is the compound between one hydrogen atom and one oxygen atom. The compound overall adopts a negative charge of 1.
If we have one hydrogen atom and one oxygen atom, the most electronegative atom is written first in chemical formulas. Therefore, the symbol for Oxygen (O) goes first.
Then, write in the hydrogen atom directly after the O symbol: OH.
Finally, since we have a negative charge on the ion, we need to play a negative sign as a superscript for the compound. Therefore, this becomes OH⁻.

Now, we need to determine the charge on the Magnesium atom which is determined from the amount of valence electrons the atom has.

On a periodic table, the symbol for Magnesium is Mg and this element has 2 valence electrons.
In order to fulfill the Octet Rule, the It is more likely to give up 2 electrons to a nonmetal than it is to gain 6, so we can safely assume that the charge is ²⁺.
We need to use the criss-cross technique to transfer the charges between the element and the ion, so the negative 1 charge goes to the Mg, which does not appear (negative 1 or positive 1 are implied) and since the magnesium has a charge of positive 2, this is the subscript for the hydroxide ion.
Therefore, our compound becomes Mg(OH)₂, and we have labeled this as magnesium hydroxide.

Now, to the number of atoms:

The new charge on Mg is 1-, so there is only one atom of Mg.
The charge is 2+ on the OH ion, so there are two atoms of H and two atoms of O.
Two atoms of oxygen, two atoms of hydrogen, and one atom of magnesium add up to be five atoms in total.

3 0

2 years ago