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
12345 [234]
3 years ago
13

How many atoms does 2.0 moles of He represent

Chemistry
1 answer:
Rudiy273 years ago
6 0

We use the following formula to calculate the number of atoms:

n (mol) = N(number of atoms) / NA

N(He) = n(mol) · NA

N(He) = 2,0 moles · 6.02·1023 = 12.04·1023 atoms

You might be interested in
Nitrogen has an atomic number of 7; therefore, it has ______ electrons in its outermost electron shell.
galina1969 [7]
it has 5 electrons in it's outermost shell.
s 2e- , p 5e-
4 0
3 years ago
A sample of salt (sodium chloride) is placed on the tip of a platinum wire. When the sample is heated on blue flame the flame tu
gulaghasi [49]
So platinum is a transition metal. In general transition metals are reducers, which means they can give the electrons they have, to the sodium atoms. Also in chemistry we look at sub orbitals rather that shells(2,8,8). So due to the energy from heat, the d orbital split as electrons move to a higher energy level. Some of the electrons are given to the sodium ions and therefore the flame changes colour to yellow. 
The excitation of the electrons is caused by them getting energy and so moving up an energy level. This energy is released and the electron returns to it's original state. The energy released, however, does not release in the same direction, but in different/various directions. Therefore the colour of the light changes as some energy is released in the surrounding.
8 0
3 years ago
Which of these charges has the greatest magnitude
Natalka [10]

Answer:

magnitude means absolute value, so the one that is greastest, like |-7| and |4| even id |-7| is a negative number, but it is still the one farthest away from 0, so |-7| is greater than |4|.

That is the way to find the greatest magnitude, but because I don't know your numbers so I can not answer your question, but this is the way to solve for it.

HOPE THIS HELPS!!!!!!!!!( IF IT DOES <u><em>PLEASE MARK ME AS BRAINLIEST )</em></u>

6 0
3 years ago
A solution is made by dissolving 0.0150 mol of HF in enough water to make 1.00 L of solution. At 26 °C, the osmotic pressure of
Alex777 [14]
Given:
M = 0.0150 mol/L HF solution
T = 26°C = 299.15 K
π = 0.449 atm

Required:
percent ionization

Solution:
First, we get the van't Hoff factor using this equation:
π = i MRT
0.449 atm = i (0.0150 mol/L) (0.08206 L atm / mol K) (299.15 K)
i = 1.219367

Next, calculate the concentration of the ions and the acid.
We let x = [H+] = [F-]
[HF] = 0.0150 - x

Adding all the concentration and equating to iM
x +x + 0.0150 - x = <span>1.219367 (0.0150)
x = 3.2905 x 10^-3

percent dissociation = (x/M) (100) = (3.2905 x 10-3/0.0150) (100) = 21.94%

Also,
percent dissociation = (i -1) (100) = (</span><span>1.219367 * 1) (100) = 21.94%</span>
7 0
3 years ago
A gas has a volume of 340.0 mL at 45.90 oC. What is the new temperature of the gas, in Kelvin, if the volume increased to 550.0
d1i1m1o1n [39]

Answer:

Solution for A gas has a volume of 340.0 mL at 45.90 degree celsius. What is the new temperature of the gas, in kelvin, if the volume increased to 550.0 mL.

Missing: oC. ‎| Must include: oC.

Explanation:

6 0
3 years ago
Other questions:
  • Hydrogen gas and bromine vapor react to form gaseous hydrogen bromide at 1300 K. The value of the equilibrium constant is 1.6 x
    9·1 answer
  • A student determined that the weight-percent recovery for his isolated caffeine proved to be 1.5%. The student was concerned, ex
    11·1 answer
  • What is the name of the branch of science that specifically studies the conversion of chemical energy to electrical energy and v
    9·2 answers
  • Help me with this please i need chem help lol
    7·1 answer
  • In an ionic bond:
    8·2 answers
  • Use the periodic table, find the neutral atom that has the same electron configuration as 1s2 2s2 2p6
    13·1 answer
  • What was one of the first series of event in the study of chemistry
    8·1 answer
  • How must the hydrogen in an acid be attached (ionically or covalently) to be an acid?
    13·1 answer
  • 47526 to the nearest 10​
    5·1 answer
  • How did Ptolemy's model of the solar system explain the apparent changes in speed and direction of the planets?
    13·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!