Answer:
TIMELINESS, RELEVANCE, AUTHORITY, ACCURACY and PURPOSE.
Explanation:
hope it helps!
Answer:
As the sun's angle changes, (because of the rotation of the earth) the sun slowly begins to shine more or less sunshine slowly. When sunsets and sunrises occur, the color of the sky changes because the sunshine is starting to fade out or in.
I put it in my own words so you don't have to worry about plagiarism :)
1.34 L of HF
Explanation:
We have the following chemical reaction:
Sn (s) + 2 HF (g) → SnF₂ (s) + H₂ (g)
First we calculate the number of moles of SnF₂:
number of moles = mass / molecular weight
number of moles of SnF₂ = 5 / 157 = 0.03 moles
From the chemical reaction we see that 1 mole of SnF₂ are produced from 2 moles of SnF₂. This will mean that 0.03 moles of SnF₂ are produced from 0.06 moles of HF.
Now at standard temperature and pressure (STP) we can use the following formula to calculate the volume of HF:
number of moles = volume / 22.4 (L/mole)
volume of HF = number of moles × 22.4
volume of HF = 0.06 × 22.4 = 1.34 L
Learn more about:
problems with gases at STP
brainly.com/question/8857334
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Answer:

Explanation:
The number of valence electrons tells us the group number of the neutral atom.
The atom has 4 valence electrons.
The atom is in group 4.