Explanation: <em>The hypothesis is a prediction, but it involves more than a guess. Most of the time, the hypothesis begins with a question which is then explored through background research. It is only at this point that researchers begin to develop a testable hypothesis.</em>
(Unless you are creating an exploratory study, your hypothesis should always explain what you expect to happen)
Explanation:
Because opposites attract, the negative charge at the bottom of the storm cloud wants to link up with the ground’s positive charge. Once the negative charge at the bottom of the cloud gets large enough, a flow of negative charge called a stepped leader rushes toward the Earth. The positive charges at the ground are attracted to the stepped leader, so positive charge flows upward from the ground. When the stepped leader and the positive charge meet, a strong electric current carries positive charge up into the cloud. This electric current is known as the return stroke. We see it as the bright flash of a lightning bolt.
Thunder and lightning occur at roughly the same time although you see the flash of lightning before you hear the thunder. This is because light travels much faster than sound
0.72 mole of oxygen would produce 320.4 kJ of heat.
<u>Explanation:</u>
CH₄ (g) + 2O₂ (g) → CO₂ (g) + 2H₂O (ℓ) + 890kJ
According to the equation,
2 moles of O₂ produces 890 kJ of heat
So, 0.72 moles of O₂ will produce:

Therefore, 0.72 mole of oxygen would produce 320.4 kJ of heat.
When the phosphate groups of the single nucleotides combine to form the backbone of the nucleic acid, energy is released. This energy is used for polymerization.
Answer: 1.9 moles SO₂
Explanation:
1) The chemical formula SO₂ shows that for every mol of SO₂ there are 1 mol of S and two moles of O.
2) Then you can state the proportion between the number of moles of SO₂ and O to find how many moles of SO₂:contains 3.8 moles of O.
1 mol SO₂ x
-------------------- = --------------------------
2 moles O 3.8 moles O
3) Now, you can clear x:
x = 3.8 moles O × 1 mol SO₂ / 2 moles O.
x = 1.9 moles SO₂.