Answer:
D) burning a candle
A demonstration that contains both physical and chemical changes will be BURNING OF A CANDLE.
<em>This is because when a candle is lighted up, on the top of it (where we see flame) the oxygen and other gases present around will be chemically changed (burned up)</em>
<em>When the wax in the top of the candle will get melted due to the heat of the fire a physical change takes places.</em>
A MOUNTAIN RANGE is a landform with high elevation and a more or less level surface
Answer:
Explanation:
<u>1) Data:</u>
a) [OH⁻] = 2.1 × 10⁻⁶ M . . . (the symbol g shown in the question is a typo)
b) pH = ?
<u>2) Formulae:</u>
<u>3) Solution:</u>
- pOH = log ( 1 / 2.1 × 10⁻⁶ ) = 5.7
- pH = 14 - pOH = 14 - 5.7 = 8.3
Answer:
H2O molecules are thus able to form an average of 4 H-bonds. H2O has a higher boiling point than NH3 because (i) the H-bonds are stronger and (ii) it contains twice as many H-bonds. H2O has a higher boiling point than HF because it contains twice as many H- bonds, despite these being individually weaker.
Explanation:
hope this is helpful
Explanation:
proton normally = atomic number
protons = 9