1.always listen to teacher
2 no eating in class
3 always have attentive listening
4 always have proper safety material
5 wear eyeglasses when needed
6 let others be able to listen
sorry I could only think of 6
Answer: 0,4278g of F and 0,4191g of Fe
Explanation: it's possible to calculate the mass of each element by multiplying the percentage (decimal) of the element by the mass of the compound.
For Fluorine (F)
0,847g * 0,5051 = 0,4278g of F
For iron (Fe)
0,847 * 0,4949 = 0,4191g of Fe
This is determined because even when the compound is decomposed, due to conservative law of mass, the decomposition process do not affect the amount of matter, so the mass of the elements remain even if they are separated from the original molecule.
At the end, the sum of the elements masses should be the total mass of the compound.
Answer: The concentration of excess
in solution is 0.017 M.
Explanation:
1. 
moles of 
1 mole of
give = 1 mole of 
Thus 0.019 moles of
give = 0.019 mole of 
2. moles of 
According to stoichiometry:
1 mole of
gives = 2 moles of 
Thus 0.012 moles of
give =
moles of 

As 1 mole of
neutralize 1 mole of 
0.019 mole of
will neutralize 0.019 mole of 
Thus (0.024-0.019)= 0.005 moles of
will be left.
![[OH^-]=\frac{\text {moles left}}{\text {Total volume in L}}=\frac{0.005}{0.3L}=0.017M](https://tex.z-dn.net/?f=%5BOH%5E-%5D%3D%5Cfrac%7B%5Ctext%20%7Bmoles%20left%7D%7D%7B%5Ctext%20%7BTotal%20volume%20in%20L%7D%7D%3D%5Cfrac%7B0.005%7D%7B0.3L%7D%3D0.017M)
Thus molarity of
in solution is 0.017 M.
Answer : The correct options are,
(B) 
(C) 
Explanation :
Boyle's Law : It is defined as the pressure of the gas is inversely proportional to the volume of the gas at constant temperature and number of moles.

or,

The relation between the pressure and volume of two gases are:

where,
= initial pressure of gas
= final pressure of gas
= initial volume of gas
= final volume of gas