| Products | λ(sec) -1 | T | Nature of the rays | Chemical and Physical properties of the product |
|---|---|---|---|---|
| Actinium A | 3·2 × 10 -4 | 36 mins. | no rays | Deposited on bodies; concentrated on the cathode in an electric field, soluble in ammonia and strong acids; volatilized at a temperature of 100° C., A and B can be separated by electrolysis. |
| Actinium B | 5·4 × 10 -3 | 2·15 mins. | α, β, γ | Same |
| ? | — | — | — | |
| Radium | — | 1300 years | α | Allied chemically to barium. |
| Emanation | 2·1 × 10 -6 | 3·8 days | α | Chemically inert gas of heavy molecular weight; condenses at -150° C. |
| Radium A (active deposit of rapid change) | 3·85 × 10 -3 | 3 mins. | α | } Deposited on surface of bodies; concentrated on cathode in electric field; soluble in strong acids; B volatized at about 700° C., A and C at about 1000° C. |
| Radium B (same) | 5·38 × 10 -4 | 21 mins. | no rays | Same |
| Radium C (same) | 4·13 × 10 -4 | 28 mins. | α, β, γ | Same |
| Radium D (active deposit of slow change) | — | about 40 | no rays | Soluble in acids; volatile below 1000° C. |
| Radium E (same) | 1·3 × 10 -6 | 6 days | β and γ | Non-volatile at 1000° C. |
| Radium F (same) | 5·6 × 10 -8 | 143 days | α | Deposited on bismuth from solution; volatile at about 1000° C., same properties as radio-tellurium and polonium. |
The products and their radiations are indicated graphically in Fig. 102 on page 448.