Answer : The mass of helium gas in the balloon is, 1.23 grams.
Explanation : Given,
Volume of helium gas = 6.9 L
First we have to calculate moles of helium gas at STP.
As we know that, 1 mole of substance occupy 22.4 L volume of gas.
As, 22.4 L volume of helium gas present in 1 mole of helium
So, 6.9 L volume of helium gas present in
of helium
Now we have to calculate the mass of helium gas.

Molar mass of He gas = 4 g/mol

Thus, the mass of helium gas in the balloon is, 1.23 grams.
I believe the answer is A. Iron
they have a negligible mass and they also have a negative charge so they have an association with the magnetic field. Do you remember polar? So electrons are negative and they attract the nucleus which is overall postivie (since protons are positive) so they act as magnetic since they both have an attraction
Answer:
how will water affect the force of friction
90% sure
Answer:
The molarity of the solution is 1.7
.
Explanation:
Molarity (M) or Molar Concentration is the number of moles of solute that are dissolved in a certain volume.
The molarity of a solution is calculated by dividing the moles of the solute by the volume of the solution:

Molarity is expressed in units
.
In this case, you know:
- moles of solute= 5.1
- volume= 3 L
Replacing:

Solving:
Molarity= 1.7 
<u><em>The molarity of the solution is 1.7 </em></u>
<u><em>.</em></u>