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3 years ago

HELP PLEASE!! Ndnsjjsjsjeh

Chemistry

1 answer:

slega [8]3 years ago

4 0

Answer:

I believe it is B.

Explanation:

because an element is a for sure pure substance and I am sure a compound is too. I appologize if I am wrong.

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How many moles of ethane, C2H6, are present if the reaction conditions are 305 K, 1.3 atm, and 2.5 L of ethane, C2H6

Xelga [282]

Answer:

n = 0.13 moles of C2H6

grams = 11 g of CO2

Explanation:

6 0

2 years ago

Dog a is given one cup of food. Dog b is given 1/2 cup of food . Dog.c is given two cups of food at the end of the year dog c we

dusya [7]

Dependent variable: Weight

Independent variable: Amount of food

Explanation:

In experiments such as the one described, there are two or more factors involved, which act as variables. Additionally, these factors can be classified as dependent or independent. The difference between these two is that the independent factor is changed on purpose by the researcher. This occurs with the amount of food as each dog receives a different amount of food and this is controlled by the researcher.

On the other hand, the dependent variable is the main factor analyzed in the experiment or the factor that is modified by the independent variable. In the experiment presented, the dependent variable is weight because in this experiment the focus is to analyze how weight changes with different amounts of food, and this factor is affected by the independent variable.

8 0

3 years ago

What is the molar mass of Fe(NO3)2?

motikmotik

I believe that the molar mass is 342.34g/mol

5 0

3 years ago

In the reaction between sodium and chlorine, which atom loses an electron? _____________ which atom gains an electron? _________

Serga [27]

Sodium loses an electron and chlorine gains an electron.

Hope this helps!

4 0

4 years ago

The density of toluene (C7H8) is 0.867 g/mL, and the density of thiophene (C4H4S) is 1.065 g/mL. A solution is made by dissolvin

nadya68 [22]

Answer:

(a) 0.039

(b) 0.384 M

Explanation:

We have the following data:

d(C₇H₈) = 0.867 g/mL

d(C₄H₄S) = 1.065 g/mL

V(C₇H₈) = 250.0 mL

mass(C₄H₄S) = 8.10 g

(a) The mole fraction of C₄H₄S in the solution is the number of moles of C₄H₄S divided into the total moles of the solution:

X(C₄H₄S) = moles C₄H₄S/ total moles

To calculate the moles, we need the molecular weight (MW) of each compound:

MW(C₄H₄S) = (4 x 12 g/mol) + (4 x 1 g/mol) + 32 g/mol = 84 g/mol

MW(C₇H₈) = (7 x 12 g/mol) + (8 x 1 g/mol) = 92 g/mol

Thus, we calculate the moles of C₄H₄S by dividing the mass into the MW(C₄H₄S):

moles C₄H₄S = mass(C₄H₄S)/MW(C₄H₄S)= 8.10 g/(84 g/mol) = 0.096 moles

Then, we have to calculate the moles of C₇H₈. First, we need the mass, obtained from the product of the density by the volume:

mass(C₇H₈)= d(C₇H₈) x V(C₇H₈) = 0.867 g/mL x 250.0 mL = 216.75 g

Thus, we divide the mass of C₇H₈ into the MW to calculate the moles of C₇H₈:

moles C₇H₈ = mass(C₇H₈)/MW(C₇H₈) = 216.75 g/(92 g/mol) = 2.35 moles

The total moles is obtained from the addition of the moles of the solute (C₄H₄S) and the solvent (C₇H₈):

total moles = moles C₄H₄S + moles C₇H₈ = 0.096 moles + 2.35 moles = 2.45 moles

Finally, we calculate the mole fraction of C₄H₄S:

X(C₄H₄S) = moles C₄H₄S/ total moles = 0.096 moles/2.45 moles = 0.039

(b) The molarity of C₄H₄S is calculated as follows:

M(C₄H₄S) = moles C₄H₄S/1 liter solution

Assuming that the total volume of the solution is the volume of solvent (C₇H₈), we calculate the molarity of C₄H₄S by dividing the moles into the volume of solvent in liters:

V(C₇H₈) = 250.0 mL = 0.250 L

M(C₄H₄S) = 0.096 moles/(0.250 L) = 0.384 mol/M = 0.384 M

(c) Assuming that the volumes of solute and solvent are additive, we can add the volumes of C₄H₄S and C₇H₈. First, we need the volume of C₄H₄S, which can be calculated from the mass and density:

V(C₄H₄S) = mass(C₄H₄S)/ d(C₄H₄S) = 8.10 g/(1.065 g/mL) = 7.606 mL = 0.0076 L

Now, we add the volumes:

total volume = V(C₇H₈) + V(C₄H₄S) = 0.250 L + 0.0076 L = 0.2576 L

Finally, we recalculate the molarity of C₄H₄S:

M(C₄H₄S)= moles C₄H₄S/ total volume = 0.096 moles/0.2576 L = 0.373 M

7 0

3 years ago