Answer:
a) 10.0 mm
b) 8.7 x 10¹³ times
Explanation:
Atom diameter = 1.06 x 10⁻¹⁰ m ________________ 100%
Nucleus diameter = 2.40 x 10⁻¹⁵ m ______________ x
x = 2.26 x 10⁻³ %
The nucleus diameter is equivalent to 2.26 x 10⁻³ % of the total atom size.
a) The Empire State Building model:
1 ft = 304.8 mm
1454 ft = 443179.2 mm
443179.2 mm______ 100%
y ______ 2.26 x 10⁻³ %
y = 10.0 mm
In this model, the diameter of the nucleus would be 10.0 mm.
b) Sphere volume: V =(4 · π · r³
)/3
V atom = (4 . π .( 0.53x10⁻¹⁰)³ )/3
V atom = 6.2 x 10⁻³¹ m³
V nucleus = (4 . π .( 1.2x10⁻¹⁵)³ )/3
V nucleus = 7.2 x 10⁻⁴⁵ m³
V atom / V nucleus = 6.2 x 10⁻³¹ m³ / 7.2 x 10⁻⁴⁵ m³
V atom / V nucleus = 8.7 x 10¹³
The atom is times 8.7 x 10¹³ larger in volume than its nucleus.
Answer:- 0.00724 moles.
Solution:- Grams of salicylic acid are given and it asks to calculate the moles.
For the moles, we divide the grams by the molar mass.
Formula of salicylic acid is 
Molar mass = 7(12.01)+6(1.01)+3(16.00)
= 84.07+6.06+48.00
= 138.13 gram per mol
We could make the dimensional analysis set up for showing unit cancellation and have the moles.

= 0.00724 moles
So, there will be 0.00724 moles of salicylic acid in it's 1.00 gram.
Answer: Yes the statement is true.
Explanation: Endorphins are chemicals produced by the human bodies to relieve stress and pain.
They are produced mainly by brain and help to transmit electrical signals within nervous system, thus are called as neurotransmitters.
They are also called as "feel good chemicals" as they can act as pain relievers and happiness booster and thus lead to better emotional health.
Answer:
The SI base unit for amount of substance is the mole. 1 grams NaOH is equal to 0.025001806380511 mole.