Answer: Braces are used by the people to correct the alignment and position of tooth or teeth in the jaw.
Explanation:
The teeth braces must have strong tensile strength and must create a constant pressure on the teeth so as to allow the straightening of the teeth.
The strong force of attraction between the molecules of the braces material that can be steel, nickel, molybdenum, copper, titanium. This makes the bracing material rigid on the teeth.
Answer:
Yes, you can compost lettuce and other salad leaves. Be careful! If the salad is covered in lots of dressing, the oils or fats in the dressing may attract rats or other animals to your compost heap.
Answer: measure the mass (48.425g) of KCl
Explanation:
To prepare the solution 0.65M KCl we must measure the mass of KCl that would be dissolved in 1L of the solution. This can be achieved by:
Molar Mass of KCl = 39 + 35.5 = 74.5g/mol
Number of mole (n) = 0.65
Mass conc of KCl = n x molar Mass
Mass conc of KCl = 0.65 x 74.5 = 48.425g
Therefore, to make 0.65M KCl, we must measure 48.425g
Answer:
The bond dissociation energy to break 4 bonds in 1 mol of CH is 1644 kJ
Explanation:
Since there are 4 C-H bonds in CH₄, the bond dissociation energy of 1 mol of CH₄ is 4 × bond dissociation energy of one C-H bond.
From the table one mole is C-H bond requires 411 kJ, that is 411 kJ/mol. Therefore, 4 C-H bonds would require 4 × 411 kJ = 1644 kJ
So, the bond dissociation energy to break 4 bonds in 1 mol of CH₄ is 1644 kJ
