Answer:
Explanation:
1) Chemical formula of sodium carbonate: <em>Na₂CO₃</em>
2) Ratio of carbon atoms:
- The number of atoms of C in the unit formula Na₂CO₃ is the subscript for the atom, which is 1 (since it is not written).
Hence, the ratio is 1 C atom / 1 Na₂CO₃ unit formula.
This is, there is 1 atom of carbon per each unit formula of sodium carbonate.
3) Calculate the number of moles in 1.773 × 10⁷ carbon atoms
- Divide by Avogadro's number: 6.022 × 10²³ atoms / mol
- number C moles = 1.773 × 10⁷ atoms / (6.022 × 10²³ atoms/mol)
- number C moles = 2.941 × 10⁻¹⁷ mol
Since, the ratio is 1: 1, the number of moles of sodium carbonate is the same number of moles of carbon atoms.
12.2 C
It has 3 significant figures now.
When you are collecting DNA, you could be looking for a few different things. A few examples could be skin cells, strands of hair, or possibly even a fingernail. Anything that comes from a person, including blood or saliva can be potential DNA that could help investigators to link a person back to a crime.
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The point of origin of a fire is the lowest point, since fire burns upwards.
High explosive: Ignite almost instantly, like dynamite and TNT. Two different types are primary and secondary.
<em>Primary: easily ignited, very sensitive to heat and friction. often used to ignite other explosives. </em>
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Low explosive: decompose slowly and include black and smokeless powder. They are the most common type of explosives, and are readily available.
Answer:
120 g of NaCl in 300 g H20 at 90 C
Explanation:
At x = 90 go vertical to the line for NaCl...then go left to the y-axis to find the solubility in 100 g H20 = 40
we want 300 g H20 so multiply this by 3 to get 120 gm of NaCl in 300 g
