Mastering Atomic Mass Calculations for the First 30 Elements

The video tutorial introduces tricks to learn atomic masses of the first 30 elements of the periodic table. For elements 1-20, two tricks are used: multiplying even atomic numbers by 2 and multiplying odd atomic numbers by 2 and adding 1. Exceptions include beryllium, nitrogen, chlorine, and argon. For elements 21-30, three tricks are introduced: multiplying numbers divisible by 7 by 2 and adding 3 to 8, multiplying even numbers by 2 and adding 4 to 8, and multiplying odd numbers by 2 and adding 5 to 8. Zinc is an exception. These tricks simplify memorizing atomic masses.

What is the trick to calculate the atomic mass of an element with an even atomic number among the first 20 elements?

• Multiply by 2

• Multiply by 2 and add 1

• Multiply by 3

• Multiply by 2 and add 2

Which element is NOT an exception when applying the tricks to the first 20 elements?

• Oxygen

• Chlorine

• Beryllium

• Nitrogen

How do you calculate the atomic mass of an element with an odd atomic number among the first 20 elements?

• Multiply by 2 and add 2

• Multiply by 2

• Multiply by 2 and add 1

• Multiply by 3

What is the atomic mass of beryllium, an exception in the first 20 elements?

• 12

• 11

• 9

• 7

What is the first trick for calculating atomic masses of elements 21 to 30?

• Multiply by 2 and add 3 to 8 if divisible by 7

• Multiply by 3 and add 2

• Multiply by 2 and add 4 to 8 if even

• Multiply by 2 and add 5 to 8 if odd

Which element among 21 to 30 is an exception to the tricks provided?

• Scandium

• Nickel

• Zinc

• Copper

How do you calculate the atomic mass of an element with an even atomic number among elements 21 to 30?

• Multiply by 3 and add 2

• Multiply by 2 and add 5 to 8

• Multiply by 2 and add 4 to 8

• Multiply by 2 and add 3 to 8

What is the atomic mass of scandium using the tricks for elements 21 to 30?

• 56

• 48

• 51

• 45

What is the atomic mass of nickel using the tricks for elements 21 to 30?

• 55

• 49

• 45

• 52

What is the atomic mass of zinc, an exception in the elements 21 to 30?

• 69

• 67

• 63

• 65