What element is this? How do you know?

1 answer:

4 0

Atom is the most basic unit of matter. They are the general term used to describe pieces of matter. But a different kind of atom makes up an element. A combination of atom of different elements creates a molecule. For example, you have water; it has a chemical formula of H2O. If you separate H from O, you have two atoms. Two atoms for hydrogen and one atom for oxygen. However, they are of different elements. And when you combine them to form H2O, you create a molecule.

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Maple syrup, which comes from the sap of maple trees, contains water and natural sugars. It's a clear, brown liquid and the suga

WITCHER [35]

Maple syrup, which comes from the sap of maple trees, contains water and natural sugars. It's a clear, brown liquid and the sugars can’t be separated byfiltration. The category is insoluble.

6 0

3 years ago

How many number of moles are present in 200. g of sodium bicarbonate (NaHCO3)

nikdorinn [45]

You can solve this problem through dimensional analysis.

First, find the molar mass of NaHCO3.

Na = 22.99 g

H = 1.008 g

C = 12.01 g

O (3) = 16 (3) g

Now, add them all together, you end with with the molar mass of NaHCO3.

22.99 + 1.008 + 12.01 + 16(3) = 84.008 g NaHCO3. This number means that for every mole of NaHCO3, there is 84.008 g NaHCO3. In simpler terms, 1 mole NaHCO3 = 84.008 g NaHCO3.

After finding the molar mass of sodium bicarbonate, now you can use dimensional analysis to solve for the number of moles present in 200. g of sodium bicarbonate.

$200. g NaHCO_3 * \frac{1 mole NaHCO_3}{84.008 g NaHCO_3}$

Cross out the repeating units which are g NaHCO3, and the remaining unit is mole NaHCO3

200. * 1 = 200

200/ 84.008 = 2.38

Notice how there are only 3 sig figs in the answer. This is because the given problem only gave three sig figs.

Your final answer is 2.38 mol NaHCO3.

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andrey2020 [161]

Answer:

Activation energy is needed so reactants can move together, overcome forces of repulsion, and to begin breaking bonds.

Explanation:

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