Answer : The mass of aluminium (Al) is 0.413 g
Solution : Given,
Volume of
at STP = 513 ml = 0.513 L ( 1 L = 1000 ml )
Molar mass of aluminium = 26.98 g/mole
First we have to calculate the moles of
.
At STP,
1 mole occupies 22.4 L volume
now, 0.513 L gives
moles of 
The moles of
= 0.0229 moles
The Net balanced chemical reaction is,

From the balanced chemical reaction, we conclude that
2 moles of Aluminium (Al) produces 3 moles of hydrogen gas
Now the number of moles of aluminium required in 0.0229 moles of hydrogen gas =
= 0.0153 moles
Now we have to calculate the mass of aluminium.
Mass of aluminium = number of moles × Molar mass = 0.0153 moles × 26.98 g/mole = 0.413 g
The mass of aluminium required is 0.413 g.
The answer is Heyyy friend in know because I took the test
The number of protons and electrons of an atom is equal
and the amount can be obtained by looking at the atomic number of that atom or
element.
The atomic numbers are:
Gold = 79
Thallium = 81
So we are looking for the element with an atomic number of
80, that is:
Mercury
Answer:
<span>Mercury (Hg)</span>
Hello!
To know the melting or boiling points of substances is extremely important:
-In a Scientific Setting, it would help identify and separate unknown substances, as the melting or boiling points are unique for each compound, and their determination is useful for identifying and separating them.
-In an Industrial Setting, it would help engineers to know the storage temperatures of compounds. Some compounds if stored at temperatures above their boiling points will evaporate and when stored at temperatures under their melting points will solidify. In some cases this behavior is undesired and knowledge of boiling and melting points is important.
Have a nice day!