1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
boyakko [2]
3 years ago
6

How many molecules of water of water are in a 821.3 g sample

Chemistry
1 answer:
svetlana [45]3 years ago
6 0

Answer: 2.744 x 1025 molecules

You might be interested in
What percentage of the total incoming radiation to the Earth reaches the ground? 20 30 40 70
weeeeeb [17]

Answer: 22.5 percent of incoming solar radiation goes directly to the surface of the Earth and is absorbed.

Explanation: Transfer of radiation through a planet's atmosphere. A planet and its atmosphere, in our solar system, can radiate back to space only as much energy as it absorbs from incoming solar radiation.

8 0
3 years ago
The substance in acid rain that makes it more acidic than natural rainwater is _____.
sasho [114]
I’m pretty sure it’s sulphur dioxide
4 0
3 years ago
Read 2 more answers
Consider the reaction CH4(g) 2O2(g)CO2(g) 2H2O(g) Using standard thermodynamic data at 298K, calculate the entropy change for th
zvonat [6]

Answer:

the entropy change for the surroundings when 1.62 moles of CH4(g) react at standard conditions is −8.343 J/K

Explanation:

The balanced chemical equation of the reaction in the question given is:

CH_{4(g)}  + 2O_{2(g)} \to CO_{2(g)} + 2 H_2O _{(g)}

Using standard thermodynamic data at 298K.

The entropy of each compound above are listed as follows in a respective order.

Entropy of (CH4(g)) = 186.264 J/mol.K

Entropy of (O2(g)) = 205.138 J/mol.K

Entropy of (CO2(g)) = 213.74 J/mol.K

Entropy of (H2O(g)) = 188.825 J/mol.K

The change in Entropy (S) of the reaction is therefore calculated as follows:

=1*S(CO2(g)) + 2*S(H2O(g)) - 1*S( CH4(g)) - 2*S(O2(g))

=1*(213.74) + 2*(188.825) - 1*(186.264) - 2*(205.138)

=  -5.15  J/mol.K

Given that :

the number of moles = 1.62 of CH4(g) react at standard conditions.

Then;

The change in entropy of the rxn = 1.62 \ mol * -5.15 \  J/mol.K

= −8.343 J/K

6 0
3 years ago
If the specific heat capacity of copper is 387 J/kg/°C, then how much energy is needed to raise the temperature of 400 g of copp
eduard

Answer:

Explanation:

mass = 400 grams * [1 kg/1000 grams] = 0.400 kg

c = 387 Joules / (oC * kg)

Δt = 55 - 30 = 25 oC

E = m*c * Δt

E = 0.4 * 387 * 25

E = 3870 Joules

5 0
3 years ago
Atmospheric pressure decreases as altitude increases. in other words, there is more air pushing down on you at sea level, and th
LuckyWell [14K]
Boiling point is the temperature at which vapour pressure equals atmospheric pressure.

As, we move at higher altitudes, atmospheric pressure decreases. Hence, temperature to reach the boiling point will decrease.

Further, boiling point is higher for longer chain compounds. Hence,<span> octane (C8H18) and octanol (C8H17OH) will have higher boiling point as compared to hexane (C6H14). Further, intermolecular forces of interaction are more stronger in octanol, due to presence of OH group, as compared to octane.

Hence, boiling points will be in following order: 
                                              Octanol > Octane > Hexane

Thus, hexane will boil first, followed by octane and lastly octanol.
</span>
7 0
3 years ago
Other questions:
  • When a substance melts, is energy being added or removed?
    5·2 answers
  • How much heat is needed to raise the temperature of a 5.0 gram block of aluminum from 22.0°c to 37.0°c?
    15·2 answers
  • The pauli exclusion principle states that no ____ electrons within an atom can have the same ____ quantum numbers.
    7·1 answer
  • What is a process of reacting an acid with a base until an equivalence point is reached
    10·1 answer
  • What do carbon hydrogen and oxygen atoms have in common
    8·1 answer
  • Make a quantitative and qualitative statement about the following:. water, carbon, iron, hydrogen gas, sucrose, table salt, merc
    7·2 answers
  • The molar mass of Cr(OH)2 is:
    8·1 answer
  • You combine 13 g of magnesium with 5 g of nitrogen to form a compound.
    11·1 answer
  • How many grams of hydrochloric acid and required to react completely with 61.8 grams of calcium hydroxide when they produce calc
    10·1 answer
  • Please help me, I don't bite. 3.
    14·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!