All categories

3 years ago

What elemental trend exists as we move down a column on the periodic table?

Chemistry

2 answers:

ella [17]3 years ago

5 0

I think it is A, but I am not sure.

Klio2033 [76]3 years ago

3 0

Answer: The correct answer is chemical reactivity of metals increases.

Explanation:

Chemical reactivity is defined as the tendency of an element to loose of gain electrons.

Metals are the elements which looses electrons and hence, their chemical reactivity will be the tendency to loose electrons. Their chemical reactivity increases as we move from top to bottom in a group. This is so because, the electron get added up in the new shell. So, the electron in the outermost orbital gets far away from the nucleus. And hence, this will be lost easily. Thus, the chemical reactivity gets increases.

Non-metals are the elements which gains electrons and hence, their chemical reactivity will be the tendency to loose electrons. Their chemical reactivity decreases as we move from top to bottom in a group. As, the electrons get added up in the new shell. So, the the electron in the outermost orbital gets far away from the nucleus. And hence, the electron will be difficult to gain. Thus, the chemical reactivity of non-metals decreases.

Hence, the correct answer is chemical reactivity of metals increases.

You might be interested in

Need help read the comment below.

BartSMP [9]

Answer:

Protective fruit

Explanation:

Angiosperm seeds grow in the middle of flower's ovaries and are covered by a defensive fruit.

8 0

3 years ago

How much energy is released when 0.40 mol C6H6(g) completely reacts with oxygen?

Vsevolod [243]

This question asksyou to apply Hess's law.
You have to look for how to add up all the reaction so that you get the net equation as the combustion for benzene. The net reaction should look something like C6H6(l)+ O2 (g)-->CO2(g) +H2O(l). So, you need to add up the reaction in a way so that you can cancel H2 and C.
multiply 2 H2(g) + O2 (g) --> 2H2O(l) delta H= -572 kJ by 3
multiply C(s) + O2(g) --> CO2(g) delta H= -394 kJ by 12
multiply 6C(s) + 3 H2(g) --> C6H6(l) delta H= +49 kJ by 2 after reversing the equation.
Then,
6 H2(g) + 3O2 (g) --> 6H2O(l) delta H= -1716 kJ
12C(s) + 12O2(g) --> 12CO2(g) delta H= -4728 kJ
2C6H6(l) --> 12 C(s) + 6 H2(g) delta H= - 98 kJ
______________________________________...
2C6H6(l) + 16O2 (g)-->12CO2(g) + 6H2O(l) delta H= - 6542 kJ
I hope this helps and my answer is right.

4 0

3 years ago

Read 2 more answers

The solubility of o2 at 20c is 1.38 x10^-3. the partial presure of o2 in the air at sea level is 0.27 atm. using henery;s law, c

netineya [11]

Answer: The solubility of oxygen at 682 torr is $4.58\times 10^{-3}M$

Explanation:

To calculate the molar solubility, we use the equation given by Henry's law, which is:

$C_{A}=K_H\times p_{A}$

Or,

$\frac{C_{1}}{C_{2}}=\frac{p_{1}}{p_2}$

where,

$C_1\text{ and }p_1$ are the initial concentration and partial pressure of oxygen gas

$C_2\text{ and }p_2$ are the final concentration and partial pressure of oxygen gas

We are given:

Conversion factor used: 1 atm = 760 torr

$C_1=1.38\times 10^{-3}M\\p_1=0.27atm\\C_2=?\\p_2=682torr=0.897atm$

Putting values in above equation, we get:

$\frac{1.38\times 10^{-3}}{C_2}=\frac{0.27atm}{0.897atm}\\\\C_2=\frac{1.38\times 10^{-3}\times 0.897atm}{0.27atm}=4.58\times 10^{-3}M$

Hence, the solubility of oxygen gas at 628 torr is $4.58\times 10^{-3}M$

4 0

3 years ago

A 0.500 m solution of a weak base has a ph of 9.75. what is the base hydrolysis constant, kb, for the weak base?

Vladimir [108]

When we have PH = 9.75
So we can get POH = 14 - 9.75 = 4.25
and when POH = - ㏒[OH-]
by substitution:
4.25 = -㏒[OH-]
∴[OH] = 5.6x10^-5
from this reaction equation:
BOH ↔ B+ + OH-
∴[OH-] = [B+]= 5.6x10^-5 M
and Equ [BOH] = 0.5 m - X
= 0.5 - (5.6x10^-5)
= 0.4999
∴ Kb = [OH-][B+]/[BOH]
= (5.6x10^-5)^2 / 0.4999
= 6.27x10^-9

8 0

3 years ago

What does weight measure?

Luda [366]

C because I’m space there’s no gravity meaning things are weightless

4 0

4 years ago

Read 2 more answers