<u>Answer:</u> The tendency of an element to react is closely related to the number of valence electrons in the element.
<u>Explanation:</u>
Chemical reactivity is defined as the tendency of an element to loose of gain electrons.
Metals tend to loose electrons and so their chemical reactivity is the tendency to loose electrons.
Non-metals tend to gain electrons and so their chemical reactivity is the tendency to gain electrons.
The number of electrons that an element will loose or gain depends on the number of valence electrons present around that element.
<u>For Example:</u> Chlorine has 7 valence electrons and need 1 electron to complete its octet, whereas sulfur has 6 valence electrons and need 2 electrons to complete its octet.
So, chlorine will gain 1 electron easily than sulfur and thus, is more reactive than sulfur.
Hence, the tendency of an element to react is closely related to the number of valence electrons in the element.
Answer: 1145.8 years
Explanation:
Half-life of carbon-14 = 5720 years
First we have to calculate the rate constant, we use the formula :


Now we have to calculate the age of the sample:
Expression for rate law for first order kinetics is given by:

where,
k = rate constant = 
t = age of sample = ?
a = let initial amount of the reactant = 100 g
x = amount decayed = 75 g
a - x = amount left after decay process = 100 - 75 = 25g
Now put all the given values in above equation, we get


The phrase that describes a characteristic of an Arrhenius base is that Arrhenius base add hydroxide ions to the solution ( answer C)
<u><em>Explanation</em></u>
Arrhenius base is a substance that increases the concentration of OH- in aqueous solution.
The Common Arrhenius base are group 1 and 2 hydroxide such as LiOH, NaOH , Ba(OH)2 among others.
for example NaOH dissociate as follows , NaOH → Na+(aq) + OH- (aq)
Answer:
The chemical formula does not show how the atoms are connected to one another.
Explanation:
With a chemical formula, you can see the types of elements that make up the compound, the number of atoms of each element in a molecule, and the chemical symbols of the elements in the compound.
Answer:
the Ray's go right through it
Explanation:
the Ray's are so small they punch right through them