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
jolli1 [7]
3 years ago
11

A sample of helium gas has a volume of 2.75 L at STP. How many grams of He are present?

Chemistry
1 answer:
il63 [147K]3 years ago
4 0
Molar mass He = 4.0 g/mol

1 mole --------- 22.4 L ( at STP )
? mole ---------- 2.75 L

2.75 x 1 / 22.4 => 0.1227 moles

1 mole He ------------ 4.0 g
0.1227 moles --------- ?

0.1227 x 4.0 / 1 => 0.4908 g of He

hope this helps!
You might be interested in
TRUE OR FALSE
Talja [164]

Answer:

True!

Explanation:

A spectrum is simply a chart or a graph that shows the intensity of light being emitted over a range of energies. Have you ever seen a spectrum before? Probably. Nature makes beautiful ones we call rainbows. Sunlight sent through raindrops is spread out to display its various colors (the different colors are just the way our eyes perceive radiation with slightly different energies).

Hope i helped!

4 0
3 years ago
An endothermic dissolution process a. absorbs energy as heat and has positive enthalpy of solution. b. releases energy as heat a
Whitepunk [10]

Answer:

a. absorbs energy as heat and has positive enthalpy of solution.

Explanation:

A reaction can either be exothermic or endothermic. An endothermic reaction, as the dissolution described in the question, is that which absorbs heat energy from the surroundings in order to start the reaction.

Because an endothermic reaction makes heat lost from the surroundings, the enthalpy (∆H) of the solution will be positive (+). ∆H is got by finding the difference between the enthalpy of the reactants and products and since the enthalpy of a product in endothermic reaction is more, the enthalpy change (∆T) will be positive.

8 0
3 years ago
Anthracite is so hard and pure it is also referred to as a _____.
Serga [27]
<span>Anthracite is also referred to as hard coal because it is so hard and pure. It is very hard and highly compacted with variety of coal that has submetallic luster. It has highest carbon content, the lowest impurities, and highest density of energy of all the coal deposits.</span>
6 0
3 years ago
SCIENCE!!!! PLEASE HELP!!! 20 POINTS
Annette [7]

Answer:

As the Earth rotates, it also moves, or revolves, around the Sun. ... As the Earth orbits the Sun, the Moon orbits the Earth. The Moon's orbit lasts 27 1/2 days, but because the Earth keeps moving, it takes the Moon two extra days, 29 1/2, to come back to the same place in our sky.

Explanation:

4 0
3 years ago
Read 2 more answers
LaShawna and her family went to Yellowstone National Park. They saw a spring called Green Dragon Spring. Steam was rising off th
sergiy2304 [10]

Yes , I agree with the statement water contains minerals

<u>Explanation:</u>

  • When LaShawna saw the steam, she said that the water must contain a lot of minerals and the statement is true.
  • Most of the water comes from the underground supply and they undergo some cleaning process and stuff.
  • Usually, mineral water comes from natural underground water supply and the springs.
  • Chemical compounds like Calcium, potassium, sodium, iron are present in water.
  • Magnesium plays an essential function in maintaining blood supply and high mineral content water helps us to prevent or lower the heart-related disease.
  • Calcium is the building block for maintaining the bone's health.

4 0
3 years ago
Read 2 more answers
Other questions:
  • ____ rain falls in areas that have air pollution.
    14·2 answers
  • Which statement best describes how dynamic equilibrium relates to a saturated solution of sodium chloride? The concentration of
    11·2 answers
  • The nucleus of the atom contains the greatest concentration of mass of an atom. which arrow is pointing at the nucleus of nitrog
    9·1 answer
  • Chemical changes ________ involve the breaking and making of chemical bonds.
    14·1 answer
  • Determine which decay process is being described in each case. the atomic number deceases by one, and the atomic mass is unchang
    12·2 answers
  • What do you mean by hydrocarbons???<br><br><br>Good night​
    9·2 answers
  • Evidence that living things have evolved over hundreds of millions years can be found in
    8·1 answer
  • PlS hurry i'm timed
    13·2 answers
  • The answer to this question
    7·2 answers
  • Please help solve this I’ll award brainliesttt
    12·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!