Answer:
it dependes on the material
Explanation:
what is the material
<u>Answer:</u> The correct answer is Option A.
<u>Explanation:</u>
A catalyst is defined as the substance which increases the rate of the reaction without actually participating in the reaction.
This substance decreases the activation energy of the reactants, so as to proceed the reaction at a faster rate by increasing their effective collisions.
It does not affect the concentration of the reactants.
For the given reaction:

If we add NO, which is acting as a catalyst will increase the rate of the reaction to produce the products which is 
Hence, the correct answer is Option A.
Answer:
An atom of neon-20 has one fewer proton and two fewer neutrons than an atom of sodium-23.
Explanation:
Neon - 20 and Sodium - 23
Neon - 20
Protons = 10
Neutrons = 10
Sodium - 23
Protons = 11
Neutrons = 12
With the information above and checking the options;
An atom of neon-20 has one fewer proton and two fewer neutrons than an atom of sodium-23.
This option is correct.
Answer:
Mass percentage → 0.074 %
[F⁻] = 741 ppm
Explanation:
Aqueous solution of flouride → [F⁻] = 0.0390 M
It means that in 1L of solution, we have 0.0390 moles of F⁻
We need the mass of solution and the mass of 0.0390 moles of F⁻
Mass of solution can be determined by density:
1g/mL = Mass of solution / 1000 mL
Note: 1L = 1000mL
Mass of solution: 1000 g
Moles of F⁻ → 0.0390 moles . 19g /1 mol = 0.741 g
Mass percentage → (Mass of solute / Mass of solution) . 100
(0.741 g / 1000 g) . 100 = 0.074 %
Ppm = mass of solute . 10⁶ / mass of solution (mg/kg)
0.741 g . 1000 mg/1g = 741 mg
1000 g . 1 kg/1000 g = 1kg
741 mg/1kg = 741 ppm