During summer, the Earth's orbit brings Australia closer to the sun (as compared to Europe during its summer), resulting in an additional 7% solar UV intensity. Coupled with our clearer atmospheric conditions, this means that Australians are exposed to up to 15% more UV than Europeans.
Answer:
The answer to your question is the letter D. 12
Explanation:
Unbalanced chemical reaction
Al(OH)₃ + H₂SO₄ ⇒ Al₂(SO₄)₃ + H₂O
Reactants Elements Products
1 Al 2
1 S 3
5 H 2
7 O 13
Balanced chemical reaction
2Al(OH)₃ + 3H₂SO₄ ⇒ Al₂(SO₄)₃ + 6H₂O
Reactants Elements Products
2 Al 2
3 S 3
12 H 12
18 O 18
Sum up the coefficients
Result = 2 + 3 + 1 + 6
= 12
The emission of the light waves ..................... which means that THE TROUGHS OF ONE WAVE AND THE CREST OF ANOTHER overlap.
When the trough and the crest of wave overlap, it results in constructive interference and the amplitude of the two waves are added together to form a larger amplitude.<span />
1) Chemical reactions produce new substances
Ans (d)
2) The symbol, Δ in a chemical reaction means that heat of supplied to the reaction.
Ans (a)
3) A skeleton equations does not show the reaction stoichiometry, i.e. the relative amounts of reactants and products.
Ans (d)
<span>In a chemical reaction, a catalyst provides an alternate reaction pathway that has lower activation energy.</span>
