5. Any capital letter indicates a new element
Parantheses mean present of a subgroup or a group of polyatomic ions in a chemical reaction.
<u>Explanation:</u>
In a chemical reaction, sometimes, a compound may be composed of group of polyatomic ions with other ions. Some of the polyatomic ions are sulfate, carbonate, nitrate, hydroxide, bicarbonate, ammonia etc.
So these polyatomic ions are formed by combining two or more elements. Thus, if the number of polyatomic ions in a compound is more than one, then we use parathesis and write those polyatomic ions in it and write the number of polyatomic ions present in the compound as subscript of the parathesis.
For example, Fe₂(SO₄)₃
So here SO₄ is a polyatomic ion and in the compound 3 atoms of SO₄ is required to neutralize the compound and thus paranthesis is used. Thus, parantheses mean present of a subgroup or a group of polyatomic ions in a chemical reaction.
It would be velocity over frequency look up equation
Answer:

Explanation:
Given that,
The specific heat of water is 4.184Jg°C
Mass, m = 600 g
Initial temperature, T₁ = 75.5°C
We need to find the final temperature. We know that heat absorbed is given by :

So, the final temperature is equal to
.
Answer:
AlCl₃ + 3NaOH → 3NaCl + Al(OH)₃
Explanation:
Problem is to balance the given chemical equation:
Equation:
AlCl₃ + NaOH → NaClO₂ + Al(OH)₃
Balancing a chemical equation involves the conservation of atoms on both sides of the equation.
We can use a very simple mathematical method to balance the above equation;
aAlCl₃ + bNaOH → cNaCl + dAl(OH)₃
a, b, c and d are coefficients that will balance the equation:
Conserving Al: a = d
Cl: 3a = c
Na: b = c
O: b = 3d
H: b = 3d
Assume that a = 1;
c = 3
b = 3
d = 1
AlCl₃ + 3NaOH → 3NaCl + Al(OH)₃
O₂ in from of the NaClO₂ flouts the rule of chemical combination