First convert each mass to moles by dividing by the molar mass.
0.347g Oxygen = 0.022 moles
0.260g Carbon = 0.022 moles
1.537g Chlorine = 0.043 moles
Divide each by smallest mole vale (0.022)
Oxygen = 0.022/0.022 = 1
Carbon = 0.022/0.022 = 1
Chlorine = 0.043/0.022 = 2
Therefore the empirical formula is COCl2
Molality= moles of solute /kg of solvent
moles of solute= mass/molar mass
moles of solute= 3.94 g / (342 g/mol)
moles of solute= 0.01 mol
molality= 0.01 mol / 0.285 kg
molality= 0.04 m
Answer:
is to examine that whether the other variables causes a change in another. The experimental setup of controlled experiments are designed to test the hypotheses. ... It allows to change more than one variable, on the condition that all other variables are controlled.
Answer: The atomic weight of silver is 107.87 amu
Explanation:
Mass of isotope silver-107 = 106.91 amu
% abundance of isotope silver -107 = 51.84% = 
Mass of isotope silver-109 = 108.90 amu
% abundance of isotope silver-109 = 48.16% = 
Formula used for average atomic mass of an element :

![A=\sum[(106.91\times 0.5184)+(108.90\times 0.4816)]](https://tex.z-dn.net/?f=A%3D%5Csum%5B%28106.91%5Ctimes%200.5184%29%2B%28108.90%5Ctimes%200.4816%29%5D)

Thus atomic weight of silver is 107.87 amu