The atoms of some elements can be made

Suppose that 3.33 g of acetone at 25.0 °C condenses on the surface of a 44.0-g block of aluminum that is initially at 25 °C. If

jeyben [28]

Answer:

68.6 °C

Explanation:

From conservation of energy, the heat lost by acetone, Q = heat gained by aluminum, Q'

Q = Q'

Q = mL where Q = latent heat of vaporization of acetone, m = mass of acetone = 3.33 g and L = specific latent heat of vaporization of acetone = 518 J/g

Q' = m'c(θ₂ - θ₁) where m' = mass of aluminum = 44.0 g, c = specific heat capacity of aluminum = 0.9 J/g°C, θ₁ = initial temperature of aluminum = 25°C and θ₂ = final temperature of aluminum = unknown

So, mL = m'c(θ₂ - θ₁)

θ₂ - θ₁ = mL/m'c

θ₂ = mL/m'c + θ₁

substituting the values of the variables into the equation, we have

θ₂ = 3.33 g × 518 J/g/(44.0 g × 0.9 J/g°C) + 25 °C

θ₂ = 1724.94 J/(39.6 J/°C) + 25 °C

θ₂ = 43.56 °C + 25 °C

θ₂ = 68.56 °C

θ₂ ≅ 68.6 °C

So, the final temperature (in °C) of the metal block is 68.6 °C.

5 0

3 years ago

What is the energy of a light wave with a frequency of 9.8 x 10^20 Hz?

Wewaii [24]

Answer:

Regions of the Electromagnetic Spectrum

Wavelength (m)Frequency (Hz)Radio> 1 x 10-1< 3 x 109Microwave1 x 10-3 - 1 x 10-13 x 109 - 3 x 1011Infrared7 x 10-7 - 1 x 10-33 x 1011 - 4 x 1014Optical4 x 10-7 - 7 x 10-74 x 1014 - 7.5 x 1014

7 0

3 years ago

Balance the following chemical equations by writing the appropriate coefficients in the blanks provided.

BartSMP [9]

Hey there!

Al + HCl → H₂ + AlCl₃

Balance Cl.

1 on the left, 3 on the right. Add a coefficient of 3 in front of HCl.

Al + 3HCl → H₂ + AlCl₃

Balance H.

3 on the left, 2 on the right. We have to start by multiplying everything else by 2.

2Al + 3HCl → 2H₂ + 2AlCl₃

Now we have 2 on the right and 4 on the left. Change the coefficient in front of HCl from 3 to 4.

2Al + 4HCl → 2H₂ + 2AlCl₃

Now, for Cl, we have 4 on the left and 6 on the right. Change the coefficient in front of HCl again from 4 to 6.

2Al + 6HCl → 2H₂ + 2AlCl₃

Now, our H is unbalanced again. 6 on the left, 4 on the right. Change the coefficient in front of H₂ from 2 to 3.

2Al + 6HCl → 3H₂ + 2AlCl₃

Balance Al.

2 on the left, 2 on the right. Already balanced.

Here is our final balanced equation:

2Al + 6HCl → 3H₂ + 2AlCl₃

Hope this helps!

5 0

3 years ago

Which type of cell is a rose thorn? prokaryotic eukaryotic plant eukaryotic animal chloroplastic

Ede4ka [16]

Plant cells are eukaryotic cells. Prokaryotic cells do not contain a membrane bound nucleus, mitochondria or other membrane bound cell structures (organelles), the DNA of prokaryotic cells are located in the cytoplasm of the cell. ... Plant cells are eukaryotic because they have a nuclear membrane.
so therefore, A rose thorn is a eukaryotic plant cell.

5 0

4 years ago

Read 2 more answers

How many grams of magnesium oxide can be produced if 25.0 g of magnesium are allowed to react with 28 g of oxygen?

Ivanshal [37]

Answer : The mass of $MgO$ produced is, 41.68 grams.

Explanation : Given,

Mass of $Mg$ = 25.0 g

Mass of $O_2$ = 28 g

Molar mass of $Mg$ = 24 g/mol

Molar mass of $O_2$ = 32 g/mol

First we have to calculate the moles of $Mg$ and $O_2$ .

$\text{Moles of }Mg=\frac{\text{Given mass }Mg}{\text{Molar mass }Mg}$

$\text{Moles of }Mg=\frac{25.0g}{24g/mol}=1.042mol$

and,

$\text{Moles of }O_2=\frac{\text{Given mass }O_2}{\text{Molar mass }O_2}$

$\text{Moles of }O_2=\frac{28g}{32g/mol}=0.875mol$

Now we have to calculate the limiting and excess reagent.

The balanced chemical equation is:

$2Mg+O_2\rightarrow 2MgO$

From the balanced reaction we conclude that

As, 2 mole of $Mg$ react with 1 mole of $O_2$

So, 1.042 moles of $Mg$ react with $\frac{1.042}{2}=0.521$ moles of $O_2$

From this we conclude that, $O_2$ is an excess reagent because the given moles are greater than the required moles and $Mg$ is a limiting reagent and it limits the formation of product.

Now we have to calculate the moles of $MgO$

From the reaction, we conclude that

As, 2 mole of $Mg$ react to give 2 mole of $MgO$

So, 1.042 mole of $Mg$ react to give 1.042 mole of $MgO$

Now we have to calculate the mass of $MgO$

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

Molar mass of $MgO$ = 40 g/mole

$\text{ Mass of }MgO=(1.042moles)\times (40g/mole)=41.68g$

Therefore, the mass of $MgO$ produced is, 41.68 grams.

4 0

3 years ago