<span>each of two or more forms of the same element that contain equal numbers of protons but different numbers of neutrons in their nuclei, and hence differ in relative atomic mass but not in chemical properties; in particular, a radioactive form of an element.</span>
The Balance Chemical equation is as follow,
2 Mg (s) + O₂(g) → 2 MgO(s)<span> + 72.3 kJ
According to this equation,
2 Moles of MgO formation involved = 72.3 kJ of Heat
So,
5 Moles of MgO formation will involve = X kJ of Heat
Solving for X,
X = (5 Moles </span>× 72.3 kJ) ÷ 2 Moles
X = 180.75 kJ of Heat
A.true (<span>Yes we are! Though the amount is so small that it really has no major effect on us. This radiation does cause some genetic mutations if it encounters the DNA of the cell, but there are many other possible sources of mutations that make it hard to clearly blame a given mutation on radiation at the levels due to ordinary daily exposure.)</span>
Answer : The isotopic representation of silicon atom is:
Explanation :
Isotope : It is defined as the element that have the same number of protons but have the different number of neutrons of each of the atom.
Isotope notation or nuclear symbol : It is also called as nuclear notation. In isotopic notation we can easily determine an isotope's mass number, atomic number, the number of neutrons and protons in the nucleus.
The general isotopic representation of an atom is:
where,
Z = Atomic number of the atom
A = Mass number of the atom
X = Symbol of the atom
As we are given that the atom is, silicon.
Atomic number of Si atom = 14
Mass number of Si atom = 29
The symbol of silicon = (Si)
The isotopic representation of silicon atom is:
Explanation:
Correct option is
D
3
The unbalanced chemical reaction is Al(s)+O
2
(g)→Al
2
O
3
(s)
Balance Al atoms by adding 2 to Al on LHS
2Al(s)+O
2
(g)→Al
2
O
3
(s)
Balance O atoms by adding
2
3
to O
2
on LHS
2Al(s)+
2
3
O
2
(g)→Al
2
O
3
(s)
Multiply the whole equation with 2.
4Al(s)+3O
2
(g)→2Al
2
O
3
(s)
This is the balanced chemical equation. The coefficient of O
2
is 3.