Answer:
B. Line 2 has a mistake
Explanation:
1. All electromagnetic waves are made of both electric and magnetic fields (hence the name electromagnetic).
2. All electromagnetic waves are transverse, and not longitudinal.
3. All electromagnetic waves can travel through space because they do not need particles to travel (like sound waves).
4. Electromagnetic waves all travel at the speed of light (299 792 458 m/s).
B is true because plants can only use nitrogen in the form of nitrates, no other living thing needs nitrogen therefore the percentage of nitrogen in the atmosphere is 79%
Answer/Explanation:
Aluminum and oxygen
Fluorine and oxygen
Ionic compounds are formed when any type of metal is combined with a non-metal such as carbon, nitrogen, oxygen, sulfur, phosphorus, and selenium.
(any)metal + nonmetal = ionic compound
Answer:
65.18% is the percent yield for this reaction.
Explanation:

Moles of salicyclic acid = 
According to reaction 1 mole of salicyclic acid gives 1 mole of aspirin .
Then 0.01449 mole of salicylic acid will give :
of asprin
Mass of 0.01449 moles of aspirin :
= 0.01449 mol × 180 g/mol = 2.6082 g
Theoretical yield of aspirin = 2.6082 g
Experimental yield of aspirin = 1.7 g
The percent yield for this reaction:


65.18% is the percent yield for this reaction.
The mass stays constant as a substance changes from a liquid to a gas.
The Law of Conservation of Mass states that, in ordinary chemical reactions, mass is neither destroyed nor created.
That is, the mass of the reactants must equal the mass of the products.
2H₂O(ℓ) ⟶ 2H₂O(g)
1 g 1 g
If the mass of liquid water is 1 g, the mass of the water vapour must be 1 g.
Even though the water vapour is a gas and you can’t see it, it still has a mass
of 1 g.