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
Explain the difference between a physical property and a chemical property
Eduardwww [97]
Physical property-  is an aspect of matter that can be observed or measured without touching changing it.

Chemical property- may only be observed by changing the chemical identity of a substance.

The difference would be that for physical property's you dont need to do anything to figure out what they are, but for chemical properties you need to change something to observe them.

5 0
3 years ago
100 points! Report on an element
Luden [163]

Hydrogen  H weight: 81

Non-metal

Hydrogen is the simplest element; an atom consists of only one proton and one electron. It is also the most plentiful element in the universe. Despite its simplicity and abundance, hydrogen doesn't occur naturally as a gas on the Earth--it is always combined with other elements.

period 1 group 1

Hydrogen is easily the most abundant element in the universe. It is found in the sun and most of the stars, and the planet Jupiter is composed mostly of hydrogen. On Earth, hydrogen is found in the greatest quantities as water.

6 0
3 years ago
Read 2 more answers
What is the hybridization of bromine in BrO2-?
kap26 [50]
<span>The hybridization of bromine must be sp^3.</span>
5 0
3 years ago
Read 2 more answers
Define shielding and effective nuclear charge. What is the connection between the two?
ivolga24 [154]

Answer:

The relation between the shielding and effective nuclear charge is given as

Z_{eff} = Z -S

where s denote shielding

z_{eff} denote effective nuclear charge

Z - atomic number

Explanation:

shielding is referred to as the repulsion of an outermost electron to the pull of electron from valence shell.  Higher the electron in valence shell higher will be the shielding effects.  

Effective nuclear charge is the amount of net positive charge that valence electron has.

The relation between the shielding and the effective nuclear charge is given as  

Z_{eff} = Z -S

wheres denote shielding

z_{eff} denote effective nuclear charge  

Z - atomic number

8 0
3 years ago
Why do people use block and teckle systems to move heavy objects?
yaroslaw [1]
H. using a pulley system can reduce the load force, over a greater distance.<span />
8 0
3 years ago
Other questions:
  • On the periodic table of elements which group is liquid gas solid and gas in
    15·1 answer
  • A metabolic pathway that ___ (oxidizes or reduces) an energy-rich source to produce ATP from ADP. Electrons are transferred from
    5·2 answers
  • Write the chemical equations showing how a buffer containing nh4cl and nh3 would neutralize added hcl and naoh (two equations).
    13·1 answer
  • Describe how an acidic solution forms when HCI is mixed in water
    8·1 answer
  • Complete and balance the following equation: NO2−(aq)+Cr2O72−(aq)→Cr3+(aq)+NO3−(aq)(acidic solution) Express your answer as a ne
    7·1 answer
  • Why do you think properties of materials used would be considered a constraint?
    5·1 answer
  • In the reaction H2SO4 + 2 NaOH -&gt; Na2SO4 + 2H2O, an equivalence point occurs when 23.1 mL of 0.2055 M NaOH is added to a 25.0
    10·1 answer
  • What is the natural process that converts radiant energy into chemical energy called?
    11·1 answer
  • 3. Use the balanced chemical equation from the last question to solve this situation: You combine 0.5 grams of Na2CO3 with exces
    8·1 answer
  • What is the resistance of a hairdryer if it is 120 volts with a current of 15 amperes?
    9·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!