Answer:
If anything but H2O were found, it would be evidence of a chemical change. Therefore, 4 is the only viable evidence that it was a physical change of H2O liquid to H2O gas.
Answer:
The tendency of metals to lose electrons inorder to get stability is called electropositive nature ofmetals. In general most of the metalslose electrons from their valence shell due to weak force of attraction on the outermost shell.
Answer:
add 1/2 to 3/4 cup salt (sodium chloride) to the gallon ziploc bag of ice.
Concentration "molarity" of H₂SO₄ in this solution:
5 × 10⁻³ mol / dm³.
<h3>Explanation</h3>
What's the concentration of H⁺ ions in this solution?
,
where
is in the unit mol / dm³.

.
What's the concentration "molarity" of H₂SO₄ in this solution?
Sulfuric acid H₂SO₄ is a strong acid. Note the subscript "2". Each mole of this acid dissolves in water to produce two moles of H⁺ ions. It takes only
of H₂SO₄ to produce twice as much H⁺ ions.
As a result, the <em>molarity</em> of H₂SO₄ is 5 × 10⁻³ mol / dm³ or 0.005 M.