Sedimentary rocks don't necessarily make fossils. Although when animals die on top of the rocks and are never moved, blown away, etc they can get trapped under the growing rock. Which is why fossils are often found in sedimentary rocks.
First you need to find the amount of mass of Na2CO3 in one moles
(Use periodic chart)
Na= 22.99 x 2 = 45.98
C = 12.01
O = 16.00 x 4 = 64.00
Add the molar masses together to get 121.99
To find how many grams are in 4 moles, times 121.99 by 4
This gives you 487.96
But the questions asks for the answer to be in kilograms nor grams, to change into kilograms divide by 1000
This gets you the answer: 0.49 kg
No polysaccharides are complex forms of carbohydrate of long sugar molecules
This one is an oxidation-rdcution equation:
<span>H2 + F2 → 2HF
How can you tell?
If the oxidation states of the atoms in the reactans are different from the oxidation states of the same atoms in the products then it is an oxidation-reduction reaction.
Both atoms H and F in the reactants have oxidation states 0.
That is a basic rule: any atom alone or bonded to the same kind of atom has oxidation state 0.
The oxidation states in HF are: H: +1, and F: -1.
So, the H increased its oxidation state, which is that ii is oxydized ; while F reduced its oxidation state so it is reduced.
Answer: H2 + F2 ----> 2HF
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