Answer: The mole ratio of Zn to ZnO is 3: 3.
Explanation:
According to law of conservation of mass, mass can be neither be created nor be destroyed. The mass on reactant side must be equal to the mass on product side. Thus the atoms of each element on both side of the reaction must be same.
The balanced chemical reaction is:

Here 3 moles of Zn combine with 2 moles of
to give 1 mole of
and 3 moles of
. Thus the mole ratio of Zn to ZnO is 3: 3.
Answer:
There are often not more than one or two independent variables tested in an experiment.
Answer:
53.1 mL
Explanation:
Let's assume an ideal gas, and at the Standard Temperature and Pressure are equal to 273 K and 101.325 kPa.
For the ideal gas law:
P1*V1/T1 = P2*V2/T2
Where P is the pressure, V is the volume, T is temperature, 1 is the initial state and 2 the final state.
At the eudiometer, there is a mixture between the gas and the water vapor, thus, the total pressure is the sum of the partial pressure of the components. The pressure of the gas is:
P1 = 92.5 - 2.8 = 89.7 kPa
T1 = 23°C + 273 = 296 K
89.7*65/296 = 101.325*V2/273
101.325V2 = 5377.45
V2 = 53.1 mL
Answer: Anna stated that ionic compounds have high melting point and low boiling point. The error in the statement is that ionic compound have low boiling point, instead ionic compounds have high boiling point, because in an ionic compound, the force of attraction working between two ions is very strong and hence the bonds present are very strong, and a lot of energy is needed to break them