Answer:
Option E, Half life = 
Explanation:
For a first order reaction, rate constant and half-life is related as:
Where,
= Half life
k = Rate constant
Rate constant given = 
So, the correct option is option E.
Answer:
Explanation:
Hello,
Based on the acting force that is applied horizontally, one can propose the following equation based on Newton's laws:
Nevertheless, since we've got a angled force, it becomes:
In this case, 
accounts for the formed angle, so the horizontal acceleration turns out into:
Best regads.
Answer:
Above pH 8.3, a blue litmus paper stays blue but turns red in an acid. A neutral solution, or one between the upper and lower values of litmus paper, pH 4.5 and 8.3, will not change the paper's color
Explanation:
Pure magnesium's formula would just be Mg because all elements except for 7 nonmetals are just left alone when they are by themselves in a formula. The 7 diatomic elements( means they have to have two of them without another element attached to it aka. a subscript two after it when it's by itself) are hydrogen, nitrogen, oxygen, fluorine, chlorine, bromine, and iodine. An easy way to remember the diatomic seven is that when looking at a periodic table if you trace over them from nitrogen over to fluorine and down to iodine all of those elements are diatomic + hydrogen.
And your unbalanced and balanced equations are correct.
(sorry I went on a tangent with the diatomic rules hopefully it will help you in the future though)
Reaction of Elemental Calcium with Water is as follow,
Ca + 2 H₂O → Ca(OH)₂ + H₂↑
When Sodium Metal is reacted with Water it produces NaOH and eliminates Hydrogen gas as shown in following equation,
2 Na + 2 H₂O → 2 NaOH + H₂↑
In both cases corresponding Hydroxides along with Hydrogen gas is produced.
