I NEED HELP PLS. I WILL GIVE 10 POINTS PLEASEEEEEEES
2 answers:
You might be interested in
The question is incomplete, here is the complete question:
Classify each element. Note that another term for main group is representative, another term for semi-metal is metalloid, and the inner transition metals are also called the lanthanide and actinide series.
Hf, Am, In, Ta, As, Se, Rn
<u>Answer:</u>
Hafnium and tantalum are transition elements.
Americium is a inner transition element.
Indium, Selenium and Radon are main group elements.
Arsenic is a metalloid.
<u>Explanation:</u>
Main group elements are the elements which belong to s block and p block. They are also known as representative elements.
S-block elements are defined as the elements whose last electron enters s-sub shell. The general electronic configuration of these elements is
P-block elements are defined as the elements whose last electron enters p-sub shell. The general electronic configuration of these elements is
Metalloids are defined as the elements which show intermediate properties between metals and non-metals. There are 7 metalloids in the periodic table. They are: Boron, Silicon, germanium, Arsenic, Antimony, Tellurium and Polonium.
Transition elements are known as d-block elements. D block elements are defined as the elements whose last electron enters d sub shell. The general electronic configuration of these elements is
Inner transition elements are known as (f block) elements. (F block) elements are defined as the elements whose last electron enters (f subshell). The general electronic configuration of these elements is . They are also known as lanthanide and actinide series.
For the given elements:
- <u>Option 1:</u> Hf
Hafnium is the 72nd element of the periodic table having electronic configuration of
As, the last electron is entering the d subshell, it is a transition element.
- <u>Option 2:</u> Am
Americium is the 95th element of the periodic table having electronic configuration of
As, the last electron is entering the (f subshell), it is a inner transition element.
- <u>Option 3:</u> In
Indium is the 49th element of the periodic table having electronic configuration of
As, the last electron is entering the p subshell, it is a main group element.
- <u>Option 4:</u> Ta
Tantalum is the 73rd element of the periodic table having electronic configuration of
As, the last electron is entering the d subshell, it is a transition element.
- <u>Option 5:</u> As
Arsenic is the 33rd element of the periodic table having electronic configuration of
As, the last electron is entering the p subshell, it is a main group element. It shows an intermediate property of metal and non-metal. Thus, it is a metalloid.
- <u>Option 6:</u> Se
Selenium is the 34th element of the periodic table having electronic configuration of
As, the last electron is entering the p subshell, it is a main group element.
- <u>Option 7:</u> Rn
Radon is the 86th element of the periodic table having electronic configuration of
As, the last electron is entering the p subshell, it is a main group element.
Considering the ideal gas law and the definition of molar mass, the molar mass of the sample of gas is 9.17 .
An ideal gas is a theoretical gas that is considered to be composed of randomly moving point particles that do not interact with each other. Gases in general are ideal when they are at high temperatures and low pressures.
The pressure, P, the temperature, T, and the volume, V, of an ideal gas, are related by a simple formula called the ideal gas law:
P×V = n×R×T
where:
- P is the gas pressure.
- V is the volume that occupies.
- T is its temperature.
- R is the ideal gas constant. The universal constant of ideal gases R has the same value for all gaseous substances.
- n is the number of moles of the gas.
The molar mass of substance is a property defined as its mass per unit quantity of substance, in other words, molar mass is the amount of mass that a substance contains in one mole.
<h3>Molar mass of the sample of gas</h3>In this case you know:
- P= 0.980 arm
- V= 1.20 L
- T= 287 K
- R= 0.082
- n= ?
Replacing in the ideal gas law:
0.980 atm× 1.20 L= n× 0.082× 287 K
Solving:
(0.980 atm× 1.20 L)÷ (0.082× 287 K)= n
<u><em>0.04997 moles= n</em></u>
On the other hand, you know that the<u><em> mass of the sample of gas</em></u> is <u><em>0.458 grams</em></u>. Replacing in the definition of molar mass:
Solving:
<u><em>molar mass= 9.17 </em></u>
Finally, the molar mass of the sample of gas is 9.17 .
Learn more about
molar mass:
ideal gas law:
#SPJ1