21

Sc

Scandium

44.95

Protons: 21

Electrons: 24

Neutrons: 21 

39

Y

Yttrium

88.90

Protons: 39

Neutrons: 50

Electrons: 39

71

Lu

Lutetium

174.96

Protons: 71

Neutrons: 104

Electrons: 71

57

La

Lanthanum

138.90

Protons: 57

Neutrons: 82

Electrons: 57

58

Ce

Cerium

140.11

Protons: 58

Neutrons: 82

Electrons: 58

59

Pr

Praseodymium

140.90

Protons: 59

Neutrons: 82

Electrons: 59

60

Nd

Neodymium

144.24

Protons: 60

Neutrons: 84

Electrons: 60

61

Pm

Promethium

144.91

Protons: 61

Neutrons: 84

Electrons: 61

62

Sm

Samarium

150.36

Protons: 62

Neutrons: 88

Electrons: 62

63

Eu

Europium

151.96

Protons: 63

Neutrons: 89

Electrons: 63

64

Gd

Gadolinium

157.25

Protons: 64 

Neutrons: 93

Electrons: 64

65

Tb

Terbium

158.92

Protons: 65

Neutrons: 94

Electrons: 65

66

Dy

Dysprosium

162.50

Protons: 66

Neutrons: 97

Electrons: 66

67

Ho

Holmium

164.93

Protons: 67

Neutrons: 98

Electrons: 67

68

Er

Erbium

167.25

Protons: 68

Neutrons: 99

Electrons: 68

69

Tm

Thulium

168.93

Protons: 69

Neutrons: 100

Electrons: 69

70

Yb

Ytterbium

173.05

Protons: 70

Neutrons: 103

Electrons: 70