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3 years ago

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According to the law of conservation of mass, mass cannot be gained or destroyed in a chemical reaction. Why can’t you simply ad

d the masses of two reactants to determine the total mass of product?

1 answer:

xxTIMURxx [149]3 years ago

6 0

Explanation:

The law of conservation of mass states that mass is conserved which also means that it cannot be created or destroyed within the isolated system.

We can add the mass of the reactant and can be equal to the mass of the product. But in some cases, it will not work like:

If reactants are not in the mole ratio, there will be a limiting reagent.

If a gas is one of reactants or products.

Radioactive decay and nuclear reactions(fission or fusion).

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Can someone help me

Sphinxa [80]

Answer: 0.24

Explanation:

$M=\frac{moles}{L}\\ M=\frac{0.6 moles}{2.5L} \\M=0.24$

4 0

3 years ago

1‑propanol ( n ‑propanol) and 2‑propanol (isopropanol) form ideal solutions in all proportions. Calculate the partial pressure a

Alex777 [14]

Answer:

$y_{prop}$ = 0.134; $y_{iso}$ = 0.866

The partial pressure of isopropanol = 34.04 Torr; The partial pressure of propanol = 5.26 Torr

Explanation:

For each of the solutions:

mole fraction of isopropanol ( $x_{iso}$ ) = 1 - mole fraction of propanol ( $x_{prop}$ ).

Given: mole fraction of propanol = 0.247. Thus, the mole fraction of isopropanol = 1 - 0.247 = 0.753.

Furthermole, the partial pressure of isopropanol = $x_{iso}$ *vapor pressure of isopropanol = 0.753*45.2 Torr = 34.04 Torr

The partial pressure of propanol = $x_{prop}$ *vapor pressure of propanol = 0.247*20.9 Torr = 5.16 Torr

Similarly,

In the vapor phase,

The mole fraction of propanol ( $y_{prop}$ ) = $\frac{P_{prop} }{P_{prop}+P_{iso}}$

Where, $P_{prop}$ is the partial pressure of propanol and $P_{iso}$ is the partial pressure of isopropanol.

Therefore,

$y_{prop}$ = 5.26/(34.04+5.16) = 0.134

$y_{iso}$ = 1 - 0.134 = 0.866

5 0

4 years ago

Calculate the masses of oxygen and nitrogen that are dissolved in of aqueous solution in equilibrium with air at 25 °C and 760 T

shtirl [24]

Explanation:

Let us assume that the volume of given aqueous solution is 7.5 L.

Therefore, according to Henry's law, the relation between concentration and pressure is as follows.

C = $\frac{P}{K_{h}}$

where, pressure (P) = 760 torr = 1 atm

According to Henry's law, constants for gases in water at $25^{o}C$ are as follows.

$p(O_{2})$ = 0.21 atm = 0.21 bar

$p(N_{2})$ = 0.78 atm = 0.78 bar

$K_{h}$ for $O_{2}$ = $7.9 \times 10^{2} bar/mol$

$K_{h}$ for $N_{2}$ = $1.6 \times 10^{3} bar /mol$

Since, 21% oxygen is present in air so, its mass will be 0.21 g. Similarly, 78% nitrogen means the mass of nitrogen is 0.78 g.

Therefore, concebtrations will be calculated as follows.

$C(O_{2}) = \frac{0.21}{7.9 \times 10^{2}} = 2.66 \times 10^-4 mol/L$

$C(N_2) = \frac{0.78}{1.6 \times 10^3} = 4.875 \times 10^-4 mol/L$

Now, we will calculate the number of moles as follows.

$n(O_{2}) = 7.5 \times 2.66 \times 10^-4 = 1.995 \times 10^-3$ mol

$n(N_2) = 7.5 \times 4.875 \times 10^-4 = 3.66 \times 10^-3$ mol

As the molar mass of $O_2$ = 32 g/mol

Hence, mass of oxygen will be as follows.

Mass of $O_2 = 32 \times 1.995 \times 10^-3 \times 1000$

= 63.84 mg

As the molar mass of $N_{2}$ = 28

Mass of $N_{2} = 28 \times 3.66 \times 10^-3$ = 102.5 mg

Thus, we can conclude that mass of oxygen is 63.84 mg and nitrogen is 102.5 mg.

5 0

4 years ago

Read 2 more answers

ASAP I AM GIVING BRAINLIEST PLEASEEEEEEEEE HELPPPPPPPPPPPPPPPPPP

zepelin [54]

Answer:

B?

Explanation:

In the example, the amount of hydrogen is 202,650 x 0.025 / 293.15 x 8.314472 = 2.078 moles. Use the mass of the hydrogen gas to calculate the gas moles directly; divide the hydrogen weight by its molar mass of 2 g/mole. For example, 250 grams (g) of the hydrogen gas corresponds to 250 g / 2 g/mole = 125 moles.

7 0

3 years ago

Calculate %ic of the interatomic bonds for the intermetallic compound al6mn. on the basis of this result, what type of interatom

pashok25 [27]

Answer : % ionic character is 0.20%

Bonding between the two metals will be purely metallic.

Explanation: For the calculation of % ionic character, we use the formula

$\% \text{ ionic character}= [1-e^{\frac{-(X_A-X_B)^2)}{4}}]\times(100\%)$

where $X_A$ & $X_B$ are the Pauling's electronegativities.

The table attached has the values of electronegativities, by taking the values of Al and Mn from there,

$X_{Al}=1.61$

$X_{Mn}=1.55$

Putting the values in the electronegativity formula, we get

$\% \text{ ionic character}= [1-e^{\frac{-(1.61-1.55)^2)}{4}}]\times(100\%)$

= 0.20%

Now, there are 3 types of inter atomic bonding

1) Ionic Bonding: It refers to the chemical bond in which there is complete transfer of valence electrons between atoms

2) Covalent Bonding: It refers to the chemical bond involving the sharing of electron pairs between 2 atoms.

3) Metallic Bonding: It refers to the chemical bond in which there is an electrostatic force between the positively charged metal ions and delocalised electrons.

In $Al_6Mn$ compound, the % ionic character is minimal that is $\sim$ 0.20% and there are two metal ions present, therefore this compound will have metallic bonding.

8 0

3 years ago