<span>Among the given choices, the third option is the only one which illustrates single replacement.
(3)H2SO4 + Mg --> H2 + MgSO4
A single replacement is also termed as single-displacement reaction, a reaction by which an element in a compound, displaces another element.
It can be illustrated this way:
X + Y-Z → X-Z + Y</span>
Answer:
The Earth's magnetic field intensity is roughly between 25,000 - 65,000 north magnetic pole is 86.50°N and 164.04°E and the south magnetic pole is 64.07°S and 135.88°E
I think the correct answer among the choices presented above is option C. The <span>atomic number of an atom is equivalent to the number of protons in the nucleus. For a neutral atom, it is also the number of electrons since in a neutral atom protons and electrons are present in equal number.</span>
Water decomposes when electrolyzed to produce hydrogen and oxygen gas. If 2.5 grams of water were decomposed 1.04 grams of oxygen will be formed.
BCA table:
2
O ⇒
+ 
B 0.13 0 + 0
C -0.13 0.065 + 0.065
A 0 0.065
Explanation:
Balanced equation for water decomposition into hydrogen and oxygen gases
2
O ⇒
+ 
B 0.13 0 + 0
C -0.13 0.065 + 0.065
A 0 0.065
Number of moles of water = 
mass = 2.5 grams
atomic mass= 18 grams
number of moles can be known by putting the values in the formula,
n = 
= 0.13 moles
2 moles of water gives one mole of oxygen on decomposition
so, 0.13 moles of water will give x moles of oxygen on decompsition
= 
x = 0.065 moles of oxygen will be formed.
moles to gram will be calculated as
mass =number of moles x atomic mass
= 0.065 x 16
= 1.04 grams of oxygen.
The answer is Cl because its oxidation number goes from a +7 down to a -1.