Pollen

How many Joules are released to cool 250.0 grams of liquid water from 100°C to 0°C? The specific heat of water is 4.180 J/g.C.

nlexa [21]

$\bold{\huge{\orange{\underline{ Solution}}}}$

$\bold{\underline{ Given :- }}$

We have 250g of liquid water and it needs to be cool at temperature from 100° C to 0° C
Specific heat of water is 4.180J/g°C

$\bold{\underline{ To \: Find :- }}$

We have to find the total number of joules released.

$\bold{\underline{ Let's \:Begin:- }}$

We know that,

Amount of heat energy = mass * specific heat * change in temperature

That is, 

$\sf{\red{ Q = mcΔT }}$

Subsitute the required values in the above formula :-

$\sf{ Q = 250 × 4.180 ×(0 - 100 )}$

$\sf{ Q = 250 × 4.180 × - 100 }$

$\sf{ Q = 250 × - 418}$

$\sf{\pink{ Q = - 104,500 J }}$

Hence, 104,500 J of heat is released to cool 250 grams of liquid water from 100° C to 0° C.

$\bold{\underline{ Now :- }}$

We have to tell whether the above process is endothermic or exothermic :-

Here, In the above process ΔT is negative and as a result of it Q is also negative that means above process is Exothermic

Exothermic process :- It is the process in which heat is evolved .
Endothermic process :- It is the process in which heat is absorbed .

4 0

2 years ago

A sample of element X contains 90% X-35 atoms, 8.0% X-37 atoms, and 2.0% X-38 atoms. The average atomic mass will be closest to

Ne4ueva [31]

To find average atomic mass you multiply the mass of each isotope by its percentage, and then add the values up.

35 * 0.90 + 37 * 0.08 + 38 * 0.02 = 35.22

Average atomic mass closest to 35.22 amu.

6 0

4 years ago

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PLEASE HELP. Give the orbital configuration of the phosphorus (p) atom.

Kipish [7]

Answer: 1s^22s^22p^63s^23p^3

Explanation:

Assuming that orbital configuration is the same as electron configuration this is the answer.

4 0

3 years ago

Read 2 more answers

If a neutral compound is composed of carbon and hydrogen and you know that it has exactly 2 carbons connected by a double bond,

Oksanka [162]

Answer: 4 hydrogens

Explanation:

This is what the structure will look like C=C. Remember that it's important that all structures have a complete octet. As it looks right now each carbon is sharing 4 valence electrons so each needs 2 more bonds to hydrogen complete its octet.

4 0

3 years ago

Read 2 more answers

Which of the following reasons best explains why it is possible to separate a 1:1 mixture of 1-chlorobutane and 1-butanol by fra

KatRina [158]

Answer:

The boiling point of 1-chlorobutane is substantially lower than that of 1-butanol

Explanation:

Fractional distillation is a separation process based on difference in boiling point of two compounds.

1-chlorobutane is a polar aprotic molecule due to presence of polar C-Cl bond. Hence dipole-dipole intermolecular force exists in 1-chlorobutane as a major force.

1-butanol is a polar protic molecule. Hence dipole-dipole force along with hydrogen bonding exist in 1-butanol.

Therefore intermolecular force is stronger in 1-butanol as compared to 1-chlorobutane.

So, boiling point of 1-butanol is much higher than 1-chlorobutane.

Hence mixture of 1-chlorobutane and 1-butanol can be separated by fractional distillation based on difference in boiling point.

So, option (D) is correct.

6 0

3 years ago