The given question is incomplete. The complete question is as follows.
A solution contains an unknown mass of dissolved barium ions. When sodium sulfate is added to the solution, a white precipitate forms. The precipitate is filtered and dried and then found to have a mass of 212 mg. What mass of barium was in the original solution? (Assume that all of the barium was precipitated out of solution by the reaction.)
Explanation:
When 
and 
are added then white precipitate forms. And, reaction equation for this is as follows.
It is given that mass (m) is 212 mg or 0.212 g (as 1 g = 1000 mg). Molecular weight of 
is 233.43.
Now, we will calculate the number of moles as follows.
No. of moles = mass × M.W
= 
= 0.00091 mol of
Hence, it means that 0.00091 mol of . Now, we will calculate the mass as follows.
Mass = moles × MW
= 
= 0.124 grams or 124 mg of barium
Thus, we can conclude that mass of barium into the original solution is 124 mg.
Answer:
Motile bacteria have flagella, while nonmotile bacteria do not.
Explanation:
Answer:
Molecules speed up when they get energy from other molecules and slow down when they give energy to other molecules.
Explanation:
We know from the first law of thermodynamics that energy can not be created nor destroyed.
However, according to the kinetic molecular theory, molecules collide frequently with each other. All molecules in a substance do not possess equal energy hence some molecules are more energetic than others.
When a more energetic molecule collides with a less energetic molecule, the more energetic molecule transfers energy to the less energetic molecule. The less energetic molecule speeds up while the molecule that collided with it slows down due to energy transfer from one molecule to another.
60mmHg = 1 atm
<span>1 mmHg = 1/760atm </span>
<span>610mmHg = 610/760 </span>
<span>= .80atm</span>
pH = 7.51. The substance is basic.
[H⁺] = 3.1 × 10⁻⁸ mol·L⁻¹.
pH = -log[H⁺] = -log(3.1 × 10⁻⁸) = 7.51
The substance is basic because <em>pH > 7</em>.
