Answer:
<em>b</em>
<em>an increase in non-biodegradable wastes</em>
Explanation:
<h3>
Answer:</h3>
Reactivity increases because the valence level is further from the nucleus of an atom.
<h3>
Explanation:</h3>
- The reactivity of elements in the periodic table depends on the position of the element in the periodic table.
- The trend in the reactivity across the period and down the group depends on whether one is dealing with metallic elements or non-metallic elements.
- Reactivity of metals such as alkali metals and alkali-earth metals increases down the group as the number of energy levels increases making valence electrons to be further from the nucleus.
- Reactivity of non-metallic groups such as halogen decreases down the group as energy levels increase which reduces the nuclear attraction of the valence electrons to the nucleus.
Half-life is the time required for the amount of something to fall to half its initial value. This term is usually used in nuclear physics to describe how quickly unstable atoms undergo decay, or how long stable atoms survive, radioactive decay, and it is also used more generally of any type of exponential or non-exponential decay.
In simpler terms: this is when an isotopes radioactivity is cut in half
Rubidium atom is your answer!
Hope this helps!<span> </span>