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4 years ago

Calculate the mass percent (m/m) of a solution prepared by dissolving 55.84 g of nacl in 152.7 g of h2o.

1 answer:

7 0

M(NaCl)=55.84 g
m(H₂O)=157.2 g

m(solution)=m(NaCl)+m(H₂O)

w(NaCl)=100m(NaCl)/m(solution)=100m(NaCl)/(m(NaCl)+m(H₂O))

w(NaCl)=100*55.84/(55.84+152.7)=26.78%

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Various members of a class of compounds, alkenes, react with hydrogen to produce a corresponding alkane. Termed hydrogenation, t

Vitek1552 [10]

<u>Answer:</u> The mass of decane produced is $1.743\times 10^2g$

<u>Explanation:</u>

To calculate the number of moles, we use the equation:

$\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}$ ......(1)

Mass of hydrogen gas = 2.45 g

Molar mass of hydrogen gas = 2 g/mol

Putting values in equation 1:, we get:

$\text{Moles of }H_2=\frac{2.45g}{2g/mol}=1.225mol$

The chemical equation for the hydrogenation of decene follows:

$C_{10}H_{20}(l)+H_2(g)\rightarrow C_{10}H_{22}(s)$

As, decene is present in excess. So, it is considered as an excess reagent.

Thus, hydrogen gas is a limiting reagent because it limits the formation of products.

By Stoichiometry of the reaction:

1 mole of hydrogen gas produces 1 mole of decane.

So, 1.225 moles of hydrogen gas will produce = $\frac{1}{1}\times 1.225=1.225mol$ of decane

Now, calculating the mass of decane by using equation 1, we get:

Moles of decane = 1.225 mol

Molar mass of decane = 142.30 g/mol

Putting values in equation 1, we get:

$1.225mol=\frac{\text{Mass of decane}}{142.30g/mol}\\\\\text{Mass of carbon dioxide}=(1.225mol\times 142.30g/mol)=174.3g=1.743\times 10^2g$

Hence, the mass of decane produced is $1.743\times 10^2g$

5 0

3 years ago

Correct name for #10 please

ira [324]

Answer:

CH₃CH(CH₃)CH(C₃H₇)CH₂CH(CH₃)₂:

4-isopropyl-2-methylpentane.

Explanation:

Step One: Draw the structure formula of this compound. Parentheses in the formula indicate substitute groups that are connected to the carbon atom to the left.

For example, the first (CH₃) indicates that the second carbon atom from the left is connected to:

the CH₃- on the left-hand side,
the -CH(C₃H₇)CH₂CH(CH₃)₂ on the right-hand side,
a hydrogen atom, and
an additional CH₃- group that replaced one hydrogen atom.

Each carbon atom in this compound is connected to four other atoms. All bonds between carbon atoms are single bonds.

The C₃H₇ in the second pair of parentheses is the condensed form of CH₃CH₂CH₂-. See the first sketch attached. Groups in parentheses are highlighted.

Step Two: Find the carbon backbone. The backbone of a hydrocarbon is the longest chain of carbon atoms that runs through the compound. See the second sketch attached. The backbone of this compound consists of seven carbon atoms and is highlighted in green. The name for this backbone shall be heptane.

Step Three: Identify and name the substitute groups.

The two substitute groups are circled in blue in the second sketch.

The one on the right -CH₃ is a methyl group.
The one on the left is branched. $\begin{aligned}\text{CH}_3-&\text{CH}-\text{CH}_3\\[-0.5em]&\;|\end{aligned}$ This group can be formed by removing one hydrogen from the central carbon atom in propane. The name for this group is isopropyl.

Step Four: Number the atoms.

Isopropyl shall be placed before methyl. Start from the right end to minimize the index number on all substitute groups. The methyl group is on carbon number two and the isopropyl group on carbon number four. Hence the name:

4-isopropyl-2-methylheptane.

5 0

3 years ago

How many moles of nitrogen trifluoride (NF3) can be produced from 9.65 mole of Fluorine gas (F2)

user100 [1]

Answer:

6.43 moles of NF₃.

Explanation:

The balanced equation for the reaction is given below:

N₂ + 3F₂ —> 2NF₃

From the balanced equation above,

3 moles of F₂ reacted to produce 2 moles of NF₃.

Finally, we shall determine the number of mole of nitrogen trifluoride (NF₃) produced by the reaction of 9.65 moles of Fluorine gas (F₂). This can be obtained as follow:

From the balanced equation above,

3 moles of F₂ reacted to produce 2 moles of NF₃.

Therefore, 9.65 moles of F₂ will react to to produce = (9.65 × 2)/3 = 6.43 moles of NF₃.

Thus, 6.43 moles of NF₃ were obtained from the reaction.

4 0

3 years ago

Alex is 1.67 meters tall. His

nekit [7.7K]

Answer: A

Explanation:

1cm=.01 so it would be 167-34

5 0