Answer:
A medium.
<h3>Explanation:</h3>
It's the material the wave is travelling through.
Answer:
6. d, 7. a
Explanation:
6. Molarity is a number of moles solute in 1 L solution.
7. 1 L solution - 2.5 mol K2CO3
20 L - x mol K2CO3
x =20*2.5/1 = 50 mol K2CO3
Molar mass(KCO3) = M(K) + M(C) + 3M(O)= 39 +12 +3*16= 99 g/mol
99 g/mol *50 mol = 4950 g KCO3 Closest answer is A.
Actually KCO3 does not exist, in reality it should be K2CO3.
It is avogrado number. One molecue of magnesium has 6.023 x 10^23 atoms
<h3>
Answer: b) 0.250 mol</h3>
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Work Shown:
Using the periodic table, we see that
- 1 mole of carbon = 12 grams
- 1 mole of oxygen = 16 grams
These are approximations and these values are often found underneath the atomic symbol. For example, the atomic weight listed under carbon is roughly 12.011 grams. I'm rounding to 2 sig figs in those numbers listed above.
So 1 mole of CO2 is approximately 12+2*16 = 44 grams. The 2 is there since we have 2 oxygens attached to the carbon atom.
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Since 1 mole of CO2 is 44 grams, we can use that to convert from grams to moles.
11.0 grams of CO2 = (11.0 grams)*(1 mol/44 g) = (11.0/44) mol = 0.250 mol of CO2
In short,
11.0 grams of CO2 = 0.250 mol of CO2
This is approximate.
We don't need to use any of the information in the table.