Answer: The atom count for each element on the reactant side of a balanced chemical equation is equal to the atom count for each element on the product side of the same equation
Explanation:
According to the law of conservation of mass, mass can neither be created nor be destroyed. Thus the mass of products formed must be equal to the mass of reactants taken.
In order to get the same mass on both sides, the atoms of each element must be balanced on both sides of the chemical equation.

Thus there are 4 atoms of hydrogen on reactant as well as product side.
Also there are 2 atoms of oxygen on reactant as well as product side.
Answer: a) 211 mm Hg
b) 0.629 grams
Explanation:
According to Dalton's law, the total pressure is the sum of individual pressures.

= total pressure = 750 mmHg
= 124 mm Hg
= 218 mm Hg
= 197 mm Hg
= ?


Thus the partial pressure of the helium gas is 211 mmHg.
b) According to the ideal gas equation:
P = Pressure of the gas = 211 mmHg = 0.28 atm (760mmHg=1atm)
V= Volume of the gas = 13.0 L
T= Temperature of the gas = 282 K
R= Gas constant = 0.0821 atmL/K mol
n= moles of gas= ?
Mass of helium= 
Thus mass of helium gas present in a 13.0-L sample of this mixture at 282 K is 0.629 grams
Um i think gold... i think?
Answer:
In fluorine, the electrons are tightly held to the nuclei. The electrons have little chance to wander to one side of the molecule, so the London dispersion forces are relatively weak. At a low enough temperature the molecules will all be solids. At a high enough temperature they will all be gases.