Explanation:
mass H2O2 = 55 mL(1.407 g/mL) = 80.85 g
molar mass H2O2 = 2(1.01 g/mol) + 2(16.00 g/mol) = 34.02 g/mol
moles H2O2 = 80.85 g/34.02 g/mol = 2.377 moles H2O2
For each mole of H2O2 you obtain 0.5 mole of O2 (see the equation).
moles O2 = 2.377 moles H2O2 (1 mole O2)/(2 moles H2O2) = 1.188 moles O2
Now, you need the temperature. If you are at STP (273 K, and 1.00 atm) then 1 mole of an ideal gas at STP has a volume of 22.4 L. Without temperature you are not really able to continue. I will assume you are at STP.
Volume O2 = 1.188 moles O2(22.4 L/mole) = 0.0530 L of O2.
which is 53 mL.
Bohr's atomic model proposed that electrons move in specific orbits around the nucleus of an atom.
Radioactivity in our world <span>b. is as old as the universe.
</span><span>Radioactive atom spontaneously emits energetic particles or waves, while decays on lighter nuclei (atoms with smaller atomic mass). Radioactivity is used to calculate how old is Earth and living things, for that purpose isotope of carbon is used.</span>
The mass decay rate is of the form
where
m₀ = 3000 g,the initial mass
k = the decay constant
t = time, years.
Because the half-life is 30 years, therefore
After 60 years, the mass remaining is
Answer: 750 g
The answer is Reduction. All three methods (convection, radiation, and conduction) are all ways of transferring heat. Convection is the transfer of heat by means of a medium such as air. Conduction is the transfer of heat from the contact of two surfaces at different temperatures. Radiation is the transfer of heat via electromagnetic waves.
Reduction is a chemical reaction that involves the gain of electrons. It is the opposite of oxidation which involves the loss of electrons.
