Rhestr elfennau yn nhrefn eu rhif
Oddi ar Wicipedia
| Rhif | Elfen | Sym. |
| 1 | hydrogen | H |
| 2 | heliwm | He |
| 3 | lithiwm | Li |
| 4 | beriliwm | Be |
| 5 | boron | B |
| 6 | carbon | C |
| 7 | nitrogen | N |
| 8 | ocsigen | O |
| 9 | fflworin | F |
| 10 | neon | Ne |
| 11 | sodiwm | Na |
| 12 | magnesiwm | Mg |
| 13 | alwminwm | Al |
| 14 | silicon | Si |
| 15 | ffosfforws | P |
| 16 | sylffwr | S |
| 17 | clorin | Cl |
| 18 | argon | Ar |
| 19 | potasiwm | K |
| 20 | calsiwm | Ca |
| 21 | scandiwm | Sc |
| 22 | titaniwm | Ti |
| 23 | vanadiwm | V |
| 24 | cromiwm | Cr |
| 25 | manganîs | Mn |
| 26 | haearn | Fe |
| 27 | cobalt | Co |
| 28 | nicel | Ni |
| 29 | copr | Cu |
| 30 | sinc | Zn |
| 31 | galiwm | Ga |
| 32 | germaniwm | Ge |
| 33 | arsenig | As |
| 34 | seleniwm | Se |
| 35 | bromin | Br |
| 36 | krupton | Kr |
| 37 | rwbidiwm | Rb |
| 38 | strontiwm | Sr |
| 39 | ytriwm | Y |
| 40 | sirconiwm | Zr |
| 41 | niobiwm | Nb |
| 42 | molybdenwm | Mo |
| 43 | technetiwm | Tc |
| 44 | rutheniwm | Ru |
| 45 | rhodiwm | Rh |
| 46 | paladiwm | Pd |
| 47 | arian | Ag |
| 48 | cadmiwm | Cd |
| 49 | indiwm | In |
| 50 | tun | Sn |
| 51 | antimoni | Sb |
| 52 | telwriwm | Te |
| 53 | ïodin | I |
| 54 | senon | Xe |
| 55 | cesiwm | Cs |
| 56 | bariwm | Ba |
| 57 | lanthanwm | La |
| 58 | ceriwm | Ce |
| 59 | praseodymiwm | Pr |
| 60 | neodymiwm | Nd |
| 61 | promethiwm | Pm |
| 62 | samariwm | Sm |
| 63 | europiwm | Eu |
| 64 | gadoliniwm | Gd |
| 65 | terbiwm | Tb |
| 66 | dysprosiwm | Dy |
| 67 | holmiwm | Ho |
| 68 | erbiwm | Er |
| 69 | thuliwm | Tm |
| 70 | yterbiwm | Yb |
| 71 | lwtetiwm | Lu |
| 72 | hafniwm | Hf |
| 73 | tantalwm | Ta |
| 74 | twngsten | W |
| 75 | rheniwm | Re |
| 76 | osmiwm | Os |
| 77 | iridiwm | Ir |
| 78 | platinwm | Pt |
| 79 | aur | Au |
| 80 | mercwri | Hg |
| 81 | thaliwm | Tl |
| 82 | plwm | Pb |
| 83 | bismwth | Bi |
| 84 | poloniwm | Po |
| 85 | astatin | At |
| 86 | radon | Rn |
| 87 | ffransiwm | Fr |
| 88 | radiwm | Ra |
| 89 | actiniwm | Ac |
| 90 | thoriwm | Th |
| 91 | protactiniwm | Pa |
| 92 | wraniwm | U |
| 93 | neptwniwm | Np |
| 94 | plwtoniwm | Pu |
| 95 | americiwm | Am |
| 96 | cwriwm | Cm |
| 97 | berkeliwm | Bk |
| 98 | californiwm | Cf |
| 99 | einsteiniwm | Es |
| 100 | fermiwm | Fm |
| 101 | mendelefiwm | Md |
| 102 | nobeliwm | No |
| 103 | lawrenciwm | Lr |
| 104 | rutherfordiwm | Rf |

