Answer:
2.93g
Explanation:first, let us calculate the number of mole of NaCl present in the solution. This is illustrated below:
Molarity = 0.5M
Volume = 100cm^3 = 100/1000 = 0.1L
Mole =?
Molarity = mole /Volume
Mole = Molarity x Volume
Mole of NaCl = 0.5 x 0.1 = 0.05mole
Now we can obtain the mass of NaCl as follows:
Molar Mass of NaCl = 23 + 35.5 = 58.5g/mol
Mole of NaCl = 0.05mol
Mass of NaCl =?
Mass = number of mole x molar Mass
Mass of NaCl = 0.05 x 58.5
Mass of NaCl = 2.93g
It's pretty easy to balance equations! Basically you want to make sure that the number of each compound is equal on both sides of the arrow.
For example number one is
Fe + H2SO4 -> Fe2(SO4)3 + H2
A 3 in front of H2SO4 because there's a subscript of 3 on the right side.
Then a 3 in front of H2 because of the previous step.
Then add a 2 in front of Fe because of the 2 subscript in Fe2(SO4)3
Then add a 1 in front of Fe2(SO4)3 because you already have an equal number of each element.
<u>2</u>Fe + <u>3</u>H2SO4 -> <u>1</u>Fe2(SO4)3 + <u>3</u>H2
I hope this explanation helps! You should really do your homework because practice is everything when it comes to chemistry. You'll need to know how to do it for exams.
answer an element and a compound
It is a scientific hypothesis. A scientific hypothesis must be testable, however there is a significantly more grounded necessity that a testable speculation must meet before it can truly be viewed as logical. This foundation comes essentially from crafted by the rationalist of science Karl Popper, and is called "falsifiability".