Red is the answer in the blank
Answer is: c. CuSO4 + 2NaOH yields Cu(OH)2 + Na2SO4.
Copper atom has oxidation number +2, sulfur atom oxidation number +6, oxygen has oxidation number-2, sodium has oxidation number +1 and hydrogen has +1 on both side of chemical reaction, so elements did not change their oxidation numbers.
Answer:
1.645 moles of excess reactant that is of magnesium metal are left over.
Explanation:
Moles of magnesium metal = 3.29 mol
Moles of HCl = 3.29 mol

According to recation, 2 moles of HCl reacts with 1 mol of magnesium metal, then 3.29 moles of HCl will react with :
of magnesium metal
Moles of HCl left = 3.29mol - 3.29 mol = 0
Moles of magnesium metal left = 3.29 mol - 1.645 mol = 1.645 mol
1.645 moles of excess reactant that is of magnesium metal are left over.
Answer:
Lowering the object near the ground decreases its <u>potential energy.</u>
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Explanation:
Potential Energy : Energy possessed by the object due to its shape ,Size and Position is called potential energy.
Example :
Change in shape and size : When you compress the spring , potential energy is introduced in it . So it expand quickly when you remove your hand.
Change in position : when you swing , after attaining maximum height (extreme ends) , the swing comes back on its on .This is because at maximum height ,the swing has<u> maximum Potential energy . </u>Hence it fall back on its on because it already has potential energy.
Potential energy(P) is given by the formula :
P = mgh
where ,
m= mass of the object
g = acceleration due to gravity
h = height of the object from the ground
If the height of the object increases from the ground , its potential energy also get increase.
<u><em>On lowering the object The height of the object from the ground reduces . So potential energy also reduces.</em></u>
It’s soft which makes It low energy