Answer: A. 
Explanation:
The quantity of heat required to raise the temperature of a substance by one degree Celsius is called the specific heat capacity.

Q = Heat absorbed = 4.56 J
m = mass of substance = 123 g
c = specific heat capacity = ?
Change in temperature ,
Putting in the values, we get:


The specific heat of a 123 g substance that requires 4.56 J of heat in order to increase its temperature by 12.32 °C is 
I'd say true.
Matter is a physical substance that occupies space.
Lets say you put random stuff in a box. That stuff is matter, filling the box.
Its common to say that matter is everything around you. You can see everything around you (almost).
Answer:
it's-D...........................
Low pH = high acidity.
HF has a very low pH, so when added to a solution, it will lower the pH of the solution and therefore make it more acidic. So the answer should be B.
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