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
goldfiish [28.3K]
3 years ago
11

What is the mass, in grams, of 7.20×1020 molecules of caffeine, c8h10n4o2?

Chemistry
2 answers:
pickupchik [31]3 years ago
3 0
To determine the mass, you need to know the molecular weight of the c8h10n4o2 . The molecular weight of <span>c8h10n4o2 would be: 8*12 + 10*1 + 4*14 + 2*16= 194g/mol.
To convert the number of molecules into moles, you need to divide it with 6.02 * 10^23. The calculation of the mass of </span>c8h10n4o2 would be: 
(7.20×10^20 molecules)  /(6.02 * 10^23 molecule/mol)  * 194g/mol= 232 * 10^-3 grams= 0.232 grams
stellarik [79]3 years ago
3 0

Answer: 0.23 grams

Explanation:

According to avogadro's law, 1 mole of every substance weighs equal to its molecular mass and contains avogadro's number 6.023\times 10^{23} of particles.

To calculate the number of moles, we use the equation:

\text{Number of moles}=\frac{\text{Given molecules}}{\text{Avogadro's number}}=\frac{7.20\times 10^{20}}{6.023\times 10^{23}}=1.2\times 10^{-3}moles

1 mole of caffeine (C_8H_{10}N_4O_2) weighs = 194 g

1.2\times 10^{-3}  moles of  (C_8H_{10}N_4O_2) weigh = \frac{194}{1}\times 1.2\times 10^{-3}=0.23g

Thus mass of caffeine (C_8H_{10}N_4O_2) is 0.23 grams.

You might be interested in
A gas is collected at 20.0 °C and 725.0 mm Hg. When the temperature is
krek1111 [17]

Answer:

676mmHg

Explanation:

Using the formula;

P1/T1 = P2/T2

Where;

P1 = initial pressure (mmHg)

P2 = final pressure (mmHg)

T1 = initial temperature (K)

T2 = final temperature (K)

According to the information provided in this question;

P1 = 725.0mmHg

P2 = ?

T1 = 20°C = 20 + 273 = 293K

T2 = 0°C = 0 + 273 = 273K

Using P1/T1 = P2/T2

725/293 = P2/273

Cross multiply

725 × 273 = 293 × P2

197925 = 293P2

P2 = 197925 ÷ 293

P2 = 676mmHg.

The resulting pressure is 676mmHg

3 0
3 years ago
If you have a density of 100 kg/L and a mass of 1000 g what is the volume (please explain)
olchik [2.2K]

Answer:  Volume =  0.01L

Explanation:

The density of a substance is given by; Density =  Mass / Volume.

In this question, Mass = 1000g, Volume = ? and Density = 100 Kg/L

For the units to be uniform, we convert 1000g to Kg = 1Kg

Therefore, Volume = Mass / Density =  1Kg / 100Kg/L = 0.01L

                     

6 0
3 years ago
C2H6 is an example of what? a)iron b)element. c)atom. d)compound
Rama09 [41]
C2H6 is a chemical compound
6 0
3 years ago
Read 2 more answers
PLZ HELP
riadik2000 [5.3K]
Too many to know in the world.
8 0
3 years ago
A 2.026g sample of a hydrate of sodium carbonate (Na2CO3) is heated to remove water. After heating, the mass of the sample is 0.
OLEGan [10]

Answer:

62.98 % of the sample of hydrate is water

Explanation:

Step 1: Data given

Mass of the sample of a hydrate of sodium carbonate (Na2CO3) = 2.026 grams

After heating, the mass of the sample is 0.750 g

Molar mass H2O = 18.02 g/mol

Step 2: Calculate mass of water

Mass water = mass of hydrate - mass of sample after heating

Mass water = 2.026 grams - 0.750 grams

Mass water = 1.276 grams

Step 3: Calculate mass % percent of water

Mass % of water = (mass of water / total mass hydrate) * 100 %

Mass % of water = (1.276 grams / 2.026 grams) *100 %

Mass % of water = 62.98 %

62.98 % of the sample of hydrate is water

7 0
3 years ago
Read 2 more answers
Other questions:
  • Select the message that most accurately fits the passage.
    13·2 answers
  • A lahar is a type of mudflow that occurs
    5·2 answers
  • The atomic number ALWAYS equals the number of <br> protons<br> neutrons<br> electons
    13·1 answer
  • What is significant about the elements within the same group of the periodic table?
    14·1 answer
  • How many grams of silver are present in 12.044 x 1023 atoms of Ag?
    10·1 answer
  • The only sure evidence for chemical reaction is
    5·2 answers
  • Shameeka is studying for an exam. She took the notes below about calcium and chlorine, which are known to form ionic bonds. Calc
    12·2 answers
  • I WILL MARK BRAINLY-EST Do you think the way we perceive food in our culture supports the guidelines in MyPlate? Explain your
    13·1 answer
  • What is the percent of O in<br> CO2?<br> (C = 12.01 amu, O = 16.00 amu)<br> [? ]%
    5·2 answers
  • Which of these is a primary characteristic used to describe a clastic sedimentary rock?
    13·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!