Answer:
The letters are a one- or two-letter symbol assigned to each. element. ... The letters represent the name of the element when it was. discovered
Explanation:
What do the letters in the boxes of the periodic table represent?
A. The letters stand for the names commonly used for the elements.
O
C. The letters are an abbreviation of the element's name in English.
O
n chemistry, a symbol is an abbreviation for a chemical element. Symbols for chemical elements normally consist of one or two letters from the Latin alphabet and are written with the first letter capitalised.
Earlier symbols for chemical elements stem from classical Latin and Greek vocabulary. For some elements, this is because the material was known in ancient times, while for others, the name is a more recent invention. For example, Pb is the symbol for lead (plumbum in Latin); Hg is the symbol for mercury (hydrargyrum in Greek); and He is the symbol for helium (a new Latin name) because helium was not known in ancient Roman times. Some symbols come from other sources, like W for tungsten (Wolfram in German) which was not known in Roman times.d
In your choices, the best answer is the mass of the reactants and the mass of the products are no equal. The chemical equilibrium can take place in a close system and can not be affected by catalyst and is a reversible reaction. The best describe should be the concentration of reactants and products are constant.
540g
Explanation:
Given parameters:
Mass of the aluminium oxide = 1020g
Unknown:
Mass of aluminium = ?
Solution:
To find the mass of the aluminium formed from this reaction, we work from the known to the unknown. The known here is the mass of the aluminium oxide.
Using this mass, find the number of moles in the aluminium and relate it using the balanced equation to that of the unknown aluminium.
From the number of moles, we can easily find the mass of the aluminium.
Solving:
Balanced equation:
2Al₂O₃ → 4Al + 3O₂
Number of moles of Al₂O₃ = 
Molar mass of Al₂O₃ = 2(27) + 3(16) = 102g/mol
Number of moles =
= 10mol
From the balanced equation:
2 moles of Al₂O₃ produced 4 moles of Al
10 moles of Al will produce
= 20moles of Al
Mass of Al = number of moles of Al x molar mass of Al = 20 x 27 = 540g
Learn more:
Number of moles brainly.com/question/13064292
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A hope it helps ur welcome
Answer:
0.6 Liters of coolant should be drained and 0.6 Liter of water should be added.
Explanation:
Volume of the radiator = 3.6 L
Percentage of antifreeze = 60%
Total volume of anti freeze in radiator = 60% of 3.6 L :

Percentage of water= 40%
Given,optimal cooling of the engine is obtained with only 50% antifreeze.
So, now we want to reduce the percentage of antifreeze from 60% to 50 %
Volume of coolant removed = x
Volume of water added = x
Volume of anti freeze removed = 60% of(x) = 0.6x
Volume of antifreeze left in radiator =50% of 3.6 L = 
1.8 Liter is the desired volume of the antifreeze.
Total volume - Removed volume = desired volume
2.16 L - 60% of( x) = 1.8 L


0.6 Liters of coolant should be drained and 0.6 Liter of water should be added.