N: 106Answer:
72 protons, 106 neutrons, 72 electrons.
Explanation:
to solve this use this simple method: APEMAN.
A= atomic number, P= Protons, E= Electrons.
M= Mass, A= atomic number, N= neutrons.
1. APE (atomic number, protons, electrons) are the same. since Hf (Hafnium) atomic number is 72, Hf has 72 protonsand ele ctrons.
2. to get Neutrons it will be mass-atomic number= neutrons.(M-A=N)
Hf mass= 178. So, 178-72= 106 neutrons.
Answer:
The factors on which the amount of energy absorbed by an endothermic reaction depends are the " physical state of the reactant and the difference in the potential energy of the reactant and the product".
Explanation:
In an endothermic reaction the factors that affects the reaction are the physical state of the reactant, which thus becomes the enthalpy. And the difference in potential energy of the reactant because if the sum of the potential energy is less than the sum of the potential energy of the product than the endothermic reaction will be positive and the reaction hence will be endothermic.
=
-
Answer:
V = 36.7L of
Explanation:
1. Write the chemical reaction for the decomposition of sodium azide:
2. Find the number of moles of produced by the decomposition of 71.4g of
:
3. Use the ideal gas equation to find the Volume of occupied by 1.65 moles of
, at the temperature and pressure given by the problem:
Solving for V:
Converting the temperature from ◦C to K:
25◦C+273.15=298.15K
Replacing values:
V=36.7L of