Answer : The balanced chemical equation is,

Explanation :
Balanced chemical equation : It is defined as the number of atoms of individual elements present on the reactant side must be equal to the number of atoms of individual elements present on product side.
The given unbalanced chemical reaction is,

This chemical reaction is an unbalanced reaction because in this reaction, the number of atoms of individual elements are not balanced.
In order to balanced the chemical reaction, the coefficient 2 is put before the
, the coefficient 3 is put before the
and the coefficient 4 is put before the
.
The energy evolved in this reaction = 
Thus, the balanced chemical reaction will be,

Answer:
5.12x10¹¹ millimeters
Explanation:
Milli is a prefix used in science and engineering to decribe the number as the exponent x10⁻³. In the prefix kilo, the number is at the exponent x10³.
5.12x10⁵ kilometers are:
5.12x10⁵ kilometers * (1000m / 1km) = 5.12x10⁸ meters
5.12x10² meters * (1m / 1000millimeters) = 5.12x10¹¹ millimeters
Answer:

Explanation:
Step 1. Determine the cell potential
<u> E°/V </u>
2×[Cr ⟶ Cr³⁺ + 3e⁻] 0.744 V
<u>3×[Cu²⁺ + 2e⁻ ⟶ Cu] </u> <u>0.3419 V
</u>
2Cr + 3Cu²⁺ ⟶ 3Cu + 2Cr³⁺ 1.086 V
Step 2. Calculate ΔG°

Answer:
Double replacement
Precipitation reaction
Explanation:
You have the reaction:
REACTANTS PRODUCTS
BaCl₂ (aq) + Na₂SO₄ (aq) ⇒ 2NaCl (aq) + BaSO₄(s)
The general form of a double replacement reaction is the following:
AB + CD ⇒ CD + AB
The reactants basically, exchanged partners. In the case of your problem, Barium(Ba) and Sodium(Na) switched places. So this makes it a double-replacement reaction.
Now how do I know it is a precipitation reaction. A precipitation reaction occurs when two solutions combine and salt is formed. Salt is solid, so how do I know that's what occured? Look at your equation again:
BaCl₂ (aq) + Na₂SO₄ (aq) ⇒ 2NaCl (aq) + BaSO₄(s)
aq means aqueous (liquid)
s means solid
If you look at the product formed in the reaction, from two solutions, it formed a solid. So this is your clue as to why it is a precipitation reaction.