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2 years ago

How many carbon atoms are contained in 84.3 g of ethyne (c2h2)?

1 answer:

7 0

To arrive at an answer in units of carbon atoms, first we must cancel out the grams by diving 84.3g C2H2 by the molar mass of C2H2 (26.038g/mol). This molar mass is calculated by adding the masses of 2 carbon atoms (12.011g/mol) and 2 hydrogen atoms (1.008g/mol). This renders units of moles of ethyne. Next multiply by Avagadro's number (6.022x10^23 atoms/mol) to cancel the moles of ethyne and reach atoms of ethyne. Finally, because there are 2 carbon atoms in C2H2, multiply by 2 atoms Carbon/1 atom C2H2 to reach the final answer of 3.90x10^24 atoms of Carbon. This answer has been rounded to three significant figures because the lowest known value of significant figures throughout the calculations was three (84.3). The entire process is as follows: 84.3g C2H2 x (1 mol C2H2)/(26.038 g C2H2) x (6.022x10^23 atoms C2H2)/(1 mol C2H2) x (1 atoms C2H2)/(2 atom C) = 3.90x10^24 atoms C

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Given: CaC2 + N2 → CaCN2 + C In this chemical reaction, how many grams of N2 must be consumed to produce 265 grams of CaCN2? Exp

weeeeeb [17]

Answer : The grams of $N_2$ consumed is, 89.6 grams.

Solution : Given,

Mass of $CaCN_2$ = 265 g

Molar mass of $CaCN_2$ = 80 g/mole

Molar mass of $N_2$ = 28 g/mole

First we have to calculate the moles of $CaCN_2$ .

$\text{Moles of }CaCN_2=\frac{\text{Mass of }CaCN_2}{\text{Molar mass of }CaCN_2}=\frac{265g}{80g/mole}=3.2moles$

The given balanced reaction is,

$CaC_2+N_2\rightarrow CaCN_2+C$

from the reaction, we conclude that

As, 1 mole of $CaCN_2$ produces from 1 mole of $N_2$

So, 3.2 moles of $CaCN_2$ produces from 3.2 moles of $N_2$

Now we have to calculate the mass of $N_2$

$\text{Mass of }N_2=\text{Moles of }N_2\times \text{Molar mass of }N_2$

$\text{Mass of }N_2=(3.2moles)\times (28g/mole)=89.6g$

Therefore, the grams of $N_2$ consumed is, 89.6 grams.

5 0

2 years ago

Read 2 more answers

Exactly 500 grams of ice are melted at a temperature of 32°f. (lice = 333 j/g.) calculate the change in entropy (in j/k). (give

denpristay [2]

Entropy Change is calculated by (Energy transferred) / (Temperature in kelvin)
deltaS = Q / T

Q = (mass)(latent heat of fusion)
Q = m(hfusion)
Q = (500g)(333J/g) = 166,500J

T(K) = 32 + 273.15 = 305.15K
deltaS = 166,500J / 305.15K
deltaS = 545.63 J/K

3 0

2 years ago

The target diol is synthesized in one step from 1-methylcyclopentene, but your lab partner exhausted the supply of that alkene.

andrezito [222]

Answer:

The reagents are $CH_{3}CH_{3}O^{-},OsO_{4},NaHSO_{3}and H_{2}O$ .

Explanation:

1-Methylenecyclopentene is treated with HBr form 1-bromo-1-methylcyclopentane, which is treated with strong base ethoxide ion and forms 1-methylcyclopent-1-ene.

This alkene is treated with osmium tetraoxide in the presence of sodium bisulfite to form target product.

The chemical reaction is as follows.

4 0

2 years ago

What mass of calcium carbonate is produced when 250 mL of 6.0 M sodium carbonate is added to 750 mL of 1.0 M calcium fluoride

Savatey [412]

Given:

Volume of Na2CO3 = 250 ml = 0.250 L

Molarity of Na2CO3 = 6.0 M

Volume of CaF2 = 750 ml = 0.750 L

Molarity of CaF2 = 1.0 M

To determine:

The mass of CaCO3 produced

Explanation:

Na2CO3 + CaF2 → CaCO3 + 2NaF

Based on the reaction stoichiometry:

1 mole of Na2CO3 reacts with 1 moles of Caf2 to produce 1 mole of caco3

Moles of Na2CO3 present = V * M = 0.250 L * 6.0 moles/L = 1.5 moles

Moles of CaF2 present = V* M = 0.750 * 1 = 0.750 moles

CaF2 is the limiting reagent

Thus, # moles of CaCO3 produced = 0.750 moles

Molar mass of CaCO3 = 100 g/mol

Mass of CaCO3 produced = 0.750 moles * 100 g/mol = 75 g

Ans: Mass of CaCO3 produced = 75 g

7 0

2 years ago

A potential energy diagram is shown. A graph is plotted with Potential Energy in KJ on the y axis and Reaction Pathway on the x

ahrayia [7]

Answer:

35 KJ.

Explanation:

The activation energy is the minimum energy that must be overcome for a reaction to take place.

In the diagram given above, the activation energy lies between the energy of the reactants and that at the peak.

Thus we can calculate the activation energy as follow:

Energy of reactants = 30 KJ

Energy at the peak = 65 KJ

Activation energy =..?

Activation energy = Energy at the peak – Energy of reactants

Activation energy = 65 – 30

Activation energy = 35 KJ

Therefore, the activation energy of th reaction is 35 KJ

3 0

2 years ago