Answer:
A particular atom will have the same number of protons and electrons and most atoms have at least as many neutrons as protons. An element is a substance that is made entirely from one type of atom. For example, the element hydrogen is made from atoms containing just one proton and one electron.
Explanation:
Volcanic eruptions are caused by earth's internal heat sources.
All the other choices are atmospheric or external earth.
Answer:
D ≈ 4.86 g/mL
Explanation:
Density = Mass over Volume
D = m/V
Step 1: Define variables
m = 13.76 g
V = 2.83 mL
D = unknown
Step 2: Substitute and Evaluate for Density
D = 13.76 g/2.83 mL
D = 4.8621908127208480565371024734982 g/mL
Step 3: Simplify
We are given 3 sig figs.
4.8621908127208480565371024734982 g/mL ≈ 4.86 g/mL
According to Clausius-Clayperon equation,
is the vapor pressure at boiling point = 760 torr
is the vapor pressure at T_{2} =638.43 torr
Temperature
Δ
Plugging in the values, we get
ln
Therefore, the boiling point of octane = 389 K - 273 = 
There are 2 Ca, 4 H (2*2) and 4 O (2+2) on the left hand side. So there should be the same number of atoms 2Ca and 4(O+H) on the right hand side. The reaction is a synthesis (making something new), rather than a decomposition (destroying something).
The answer is Two molecules of Ca(OH)2 should be produced during the synthesis reaction.
