A neutron, I'm technically not really guessing but I'm kind of guessing because there's only 3 particles in a atom, a proton, neutron and electron, for only protons and neutrons live in the nucleus so be deduction would be neutrons.
Answer:
1.096g
Explanation:
You must know the atomic mass of Hydrogen, Fluorine, and Sodium before you can start:
Hydrogen: 1.008g/mol
Fluorine: 18.99g/mol
Sodium: 22.98g/mol
Next, find the composition percentage of NaF
22.98 + 18.99 = 41.97
Fluorine is 18.99/41.97 =45.25%
Sodium is 100-45.25 = 54.75%
Ultimately we want to know about HF so find how much F is in 2.3g: 2.3 * 0.4525 = 1.041g
Find comp. percentage of HF
18.99+1.008 = 19.998; H/total F/total
Hydrogen 5.041%
Fluorine 94.959%
Laws of conservation of say we have 1.041g of fluorine in our HF. We know 1.041 is 94.959% of the mass of HF so do some simple math to find the remaining: 1.041/0.94959 = 1.096g
The answers that are correct are a, b, and d
Answer:

Explanation:
The formula for efficiency is

Data:
Useful energy = 3 J
Energy input = 30 J
Calculation:

Answer:
Distillation
Explanation:
The method of distillation can be used to separate the two liquids, if their boiling point is known. The liquid with lower boiling point will be evaporated and its vapours will be captured, while the liquid with higher boiling point will remail in the container in the liquid state.