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If 45.0 mL of ethanol (density = 0.789 g/mL) initially at 8.0 ∘C is mixed with 45.0 mL of water (density = 1.0 g/mL) initially a

strojnjashka [21]

Answer : The final temperature of the mixture is, $22.14^oC$

Explanation :

First we have to calculate the mass of ethanol and water.

$\text{Mass of ethanol}=\text{Density of ethanol}\times \text{Volume of ethanol}=0.789g/mL\times 45.0mL=35.5g$

and,

$\text{Mass of water}=\text{Density of water}\times \text{Volume of water}=1.0g/mL\times 45.0mL=45.0g$

Now we have to calculate the final temperature of the mixture.

In this problem we assumed that heat given by the hot body is equal to the heat taken by the cold body.

$q_1=-q_2$

$m_1\times c_1\times (T_f-T_1)=-m_2\times c_2\times (T_f-T_2)$

where,

$c_1$ = specific heat of ethanol = $2.42J/g^oC$

$c_2$ = specific heat of water = $4.18J/g^oC$

$m_1$ = mass of ethanol = 35.5 g

$m_2$ = mass of water = 45.0 g

$T_f$ = final temperature of mixture = ?

$T_1$ = initial temperature of ethanol = $8.0^oC$

$T_2$ = initial temperature of water = $28.6^oC$

Now put all the given values in the above formula, we get:

$35.5g\times 2.42J/g^oC\times (T_f-8.0)^oC=-45.0g\times 4.18J/g^oC\times (T_f-28.6)^oC$

$T_f=22.14^oC$

Therefore, the final temperature of the mixture is, $22.14^oC$

3 0

3 years ago

Write a variable expression that represents the following word phrase: three more than two times the difference of x and one.

Inga [223]

Convert the wordphrase to expression

$\\ \rm\longmapsto 2(x-1)+3$

$\\ \rm\longmapsto 2x-2+3$

$\\ \rm\longmapsto 2x+1$

5 0

3 years ago

Read 2 more answers

If a man has a mass of 83 kilograms on Earth, what will the force of gravity on his body be on the moon? A. 135.6 N B. 318.5 N C

diamong [38]

First, we need to know what's the gravity value in the moon. it is 1.622 m/ s2

to find the force, let's recall this formula----> Force= mass x gravity

force= 83 kg x 1.622= 134.6

A is the closest choice.

4 0

3 years ago

Read 2 more answers

5.0 x 10^24 molecules equal

Ratling [72]

<span>4.999999999999999e</span>+<span>24 this is what i got on the calculator but i dont know if its right.</span>

8 0

3 years ago

A dehydration reaction starting with 3.8 g cyclohexanol produces 2.6 g cyclohexene. Calculate the theoretical yield for this rea

diamong [38]

Answer:

Theoretical yield of C6H10 = 3.2 g.

Explanation:

Defining Theoretical yield as the quantity of product obtained from the complete conversion of the limiting reactant in a chemical reaction. It can be expressed as grams or moles.

Equation of the reaction

C6H11OH --> C6H10 + H2O

Moles of C6H11OH:

Molar mass of C6H110H = (12*6) + (1*12) + 16

= 100 g/mol

Mass of C6H10 = 3.8 g

number of moles = mass/molar mass

=3.8/100

= 0.038 mol.

Using stoichoimetry, 1 moles of C6H110H was dehydrated to form 1 mole of C6H10 and 1 mole of water.

Therefore, 0.038 moles of C6H10 was produced.

Mass of C6H10 = molar mass * number of moles

Molar mass of C6H10 = (12*6) + (1*10)

= 82 g/mol.

Mass = 82 * 0.038

= 3.116 g of C6H10.

Theoretical yield of C6H10 = 3.2 g

4 0

3 years ago