Evaporation is one change.
Answer:
9
Explanation:
mass number = protons + neutrons
= 4 + 5 = 9
Answer:
number of protons =17
number of neutrons=20
number of electrons=17
Atomic number is the same as proton number
To find the neutrons
subtract the atomic number from the mass number
thus, Neutrons =Mass number - Atomic number
<em>Neut</em><em>rons</em><em>=</em><em>3</em><em>7</em><em>-</em><em>1</em><em>7</em>
<em>Neutr</em><em>ons</em><em>=</em><em>2</em><em>0</em>
(A) 14.8 g → 1.48 × 10^7 µg
The prefix µ means “× 10^(-6)”, so 1 µg = 1 × 10^(-6) g
The conversion factor (CF) = 1 µ g/1 × 10^(-6) g
∴ Mass = 14.8 g × [1 µg/1 × 10^(-6) g] = 1.48 × 10^7 µg
(B) 3.72 g → 3.72× 10^(-3) kg
The prefix k means “× 10^3”, so 1 kg = 1 × 10^3 g
CF = 1 kg/1 × 10^3 g
∴ Mass = 3.72 g × [1 kg/1 × 10^3 g] = 3.72× 10^(-3) kg
(C) 7.5 × 10^4 J → 75 kJ
CF = 1 kJ/1 × 10^3 J
∴ Energy = 7.5 × 10^4 J × [1 kJ/1 × 10^3 J] = 3.72× 10^(-3) kJ = 7.5 × 10^1 kJ
= 75 kJ
Answer:
Explanation:
Magnetic materials are always made of metal, but not all metals are magnetic. Iron is magnetic, so any metal with iron in it will be attracted to a magnet. Steel contains iron, so a steel paperclip will be attracted to a magnet too. Most other metals, for example aluminium, copper and gold, are NOT magnetic.