Answer:
In 1851 gold-seekers from around the world began pouring into the colonies, changing the course of Australian history. The gold rushes greatly expanded Australia's population, boosted its economy, and led to the emergence of a new national identity.
Explanation:
Answer: - 436.5 kJ.
Explanation:
According to Hess’s law of constant heat summation, the heat absorbed or evolved in a given chemical equation is the same whether the process occurs in one step or several steps.
According to this law, the chemical equation can be treated as ordinary algebraic expression and can be added or subtracted to yield the required equation.
The given chemical reaction is,
Now we have to determine the value of 
for the following reaction i.e,
According to the Hess’s law, if we divide the reaction by half then the will also get halved and on reversing the reaction , the sign of enthlapy changes.
So, the value 
for the reaction will be:
Hence, the value of for the reaction is -436.5 kJ.
I believe the answer is "Bohr's model explains the chemical behavior of all atoms."
the correct answer is A.
Each atom has three sub particles, which are electron, proton and neutron. To get the atomic mass for each atom, one has to add the masses of the proton, neutron and electron in an atom. For each atom, the major contributors to its mass are proton and neutron, this is because the mass of the electron is very small indeed. Thus, the atomic mass of an element is usually in the range of its mass number, which is obtained by the summation of proton and neutron. Since it is the number of proton that indicate an atomic number and it is the mass number that indicate atomic mass, therefore, atomic mass can be greater than the atomic number.
