What property can be used to separate oil from milk?

A 25.0 g sample of an alloy was heated to 100.0 oC and dropped into a beaker containing 90 grams of water at 25.32 oC. The tempe

elena55 [62]

Answer:

The specific heat of the alloy $C_{a} = 0.37 \frac{KJ}{Kg K}$

Explanation:

Mass of an alloy $m_{a}$ = 25 gm

Initial temperature $T_{a}$ = 100°c = 373 K

Mass of water $m_{w}$ = 90 gm

Initial temperature of water $T_{w}$ = 25.32 °c = 298.32 K

Final temperature $T_{f}$ = 27.18 °c = 300.18 K

From energy balance equation

Heat lost by alloy = Heat gain by water

$m_{a}$ $C_{a}$ [ $T_{a}$ - $T_{f}$ ] = $m_{w}$ $C_w$ ( $T_{f}$ - $T_{w}$ )

25 × $C_{a}$ × ( 373 - 300.18 ) = 90 × 4.2 (300.18 - 298.32)

$C_{a} = 0.37 \frac{KJ}{Kg K}$

This is the specific heat of the alloy.

4 0

3 years ago

How many moles of mercury are equivalent to 3.46 x 1023 atoms?

olga55 [171]

Answer:

3.02 X1023 atoms Ag limol. - - 0.50 1 moles. 6.02241023 atoms.

4 0

2 years ago

Calculate the percent yield when 500 grams of carbon dioxide react with an excess of water to produce 640 grams of carbonic acid

Elena-2011 [213]

Answer:

Percent yield = 90.5%

Explanation:

Given data:

Mass of carbon dioxide = 500 g

Mass of water = excess

Actual yield of carbonic acid = 640 g

Percent yield = ?

Solution:

Balanced chemical equation:

CO₂ + H₂O → H₂CO₃

Number of moles of carbon dioxide

Number of moles = Mass / molar mass

Number of moles = 500 g/ 44 g/mol

Number of moles = 11.4 mol

Now we will compare the moles of H₂CO₃ with CO₂.

CO₂ : H₂CO₃

1 : 1

11.4 : 11.4

Mass of carbonic acid:

Mass = number of moles × molar mass

Mass = 11.4 mol × 62.03 g/mol

Mass = 707.14 g

Percent yield:

Percent yield = actual yield / theoretical yield × 100

Percent yield = 640 g/ 707.14 g × 100

Percent yield = 90.5%

7 0

3 years ago

Why isn't geothermal energy used more often?

lianna [129]

Geothermal energy is not used more often because it's hard to find geothermal energy sources that are close to the surface (Option A).

<h3>What is Geothermal energy?</h3>

Geothermal energy is a special type of sustainable renewable source of clean energy that emerges from thermal (temperature) differences on the Earth, e.g., within geysers and similar geological formations.

In conclusion, geothermal energy is not used more often because it's hard to find geothermal energy sources that are close to the surface (Option A).

Learn more about Geothermal energy here:

brainly.com/question/19666326

#SPJ1

5 0

1 year ago

Draw the Lewis structure for BCl3. How many single bonds, double bonds, triple bonds, and unshared pairs of electrons are on the

andreev551 [17]

Answer : The number of single bonds, double bonds, triple bonds, and unshared pairs of electrons on the central atom are, 3, 0, 0 and 0 respectively.

Explanation :

Lewis-dot structure : It shows the bonding between the atoms of a molecule and it also shows the unpaired electrons present in the molecule.

In the Lewis-dot structure the valance electrons are shown by 'dot'.

The given molecule is, $BCl_3$

As we know that boron has '3' valence electrons and chlorine has '7' valence electrons.

Therefore, the total number of valence electrons in $BCl_3$ = 3 + 3(7) = 24

According to Lewis-dot structure, there are 6 number of bonding electrons and 18 number of non-bonding electrons.

From the Lewis-dot structure we conclude that,

The number of single bonds, double bonds, triple bonds, and unshared pairs of electrons on the central atom are, 3, 0, 0 and 0 respectively.

3 0

3 years ago