Answer: A.Light travels in a straight line., B.Light behaves in a predictable way. , D.Light curves around corners or obstructions
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Nitrogen makes up around 78% of the total atmosphere.
Answer:
1027.62 g
Explanation:
For 
:-
Mass of = 296.1 g
Molar mass of = 27.66 g/mol
The formula for the calculation of moles is shown below:
Thus,
From the balanced reaction:-
1 mole of react with 3 moles of oxygen
Thus,
10.705 mole of react with 3*10.705 moles of oxygen
Moles of oxygen = 32.115 moles
Molar mass of oxygen gas = 31.998 g/mol
<u>Mass = Moles * Molar mass = 32.115 * 31.998 g = 1027.62 g</u>
<span>Helium = 1
Carbon = 8
Nitrogen = 8
Strontium = 52
Tellurium = 71
If you look on a periodic table, on each element there is a number on
the top left. This represents the number of protons in an atom. Protons
have a mass of 1 (in relative to Carbon-13)
If we take nitrogen-15 for example; The number 15 tells you that the
isotope has a mass of 15. Now if you look on the periodic table,
Nitrogen has a proton number of 7. Only protons and neutrons have a
mass, electrons are considered to be negligable. Therefore the number of
neutrons Nitrogen-15 contains is 15 - 7 = 8 </span>
Answer:
Explanation:
Ions which will be definitely absent -
Ag⁺ , Hg₂⁺ , Pb⁺², because their chlorides are insoluble in water.
Ba⁺² ,Ca⁺² because their carbonates are insoluble in water,
Ions which will be definitely present
Cu⁺² , Pb⁺² . Hg⁺² , Sb⁺³ , Sn⁺² , because their sulphides are insoluble at pH = 8.
For the rest nothing can be said.
