Answer:
Transition metals, alkali metals, alkaline earth metals Transition metals - Middle of the periodic chart, only average reactivity. alkali metals - As mentioned above, very reactive. Bad choice, going from lower reactivity to higher reactivity.
Hope this answer is right!
A solution is a mixture of two or more substances combined so that it is uniform, which means you cannot see the components. <span />
The energy density is calculated by dividing the energy given by the mass of the material. From this item, the energy is 78 kcal and the mass is 50 grams. Performing the operation will give us an answer of 1.56 kcal/grams.
When a half-life passes, only half of the mass of the sample stays. So to get to 25 g from 200, let's see how much half-lives will pass.
200÷2=100
100÷2=50
50÷2=25
The answer to that is 3 half-lives, or
3 × 5730 = 17190 years
