Answer:
24.7 amu
Explanation:
An isotope is when an element can have different number of neutrons but they have same number of protons.
In order to calculate the average atomic mass with the given information do the following operations:
First change de percentages to fractional numbers, divide by 100.
I like to make a table, to organize all data and I believe is easier to understand.
65/100 = 0.65
35/100 = 0.35
% fraction
65.0 0.65
35.0 0.35
total100.0 1
Now multiply each mass with their corresponding fraction
24 (0.65) = 15.6
26 (0.35) = 9.1
% fraction uma uma
65.0 0.65 24 15.6
35.0 0.35 26 9.1
total100.0 1 24.7
Finally you add the resulting mass and the units will be in uma.
15.6+9.1 = 24.7
Therefore the average atomic mass of this element will be 24.7 uma.
Check the table in the document attached
1) Molecular formula of ammonium sulfide
(NH4)2 S
2) That means that there are 2*4 = 8 atoms of hydrogen in each molecule of ammoium sulfide, so in 5.20 mol of molecules will be 8 * 5.20 mol = 41.6 moles of atoms of hydrogen
3) To pass to number of atoms multiply by Avogadro's number: 6.022 * 10^23
41.6 moles * 6.022 * 10^23 atoms / mol = 250.5 * 10^23 = 2.50 * 10^25 atoms
Answer: 2.50 * 10^25
Answer:
Functional group
Explanation:
Functional group is specific group of atom or bond associated to an organic compound that determines the chemical properties of that compound. This atom is bonded in a certain way or specific arrangement to give the compound a peculiar physical and chemical characteristics.
Functional group like the alkyl group -CH3 is found in organic compound series like the alkane family. The chemical properties specific to the alkyl group will be active in the compound of alkane family because of the presence of the functional group Alkyl(-CH3). The functional group also plays a major role in the chemical reactivity of the compound. For example the functional group of alkyl are often non reactive, this non reactive nature will definitely rub off on the chemical properties of the compound it is attached.
Functional group like -OH is usually found in Alcohol . Due to the presence of this functional group (-OH) alcohol possess a peculiar chemical properties. The compounds possess an hydrogen bond which invariably lead to the higher boiling points of the alcohol compounds. Other functional group can be bonds like double bond found in alkene compound or triple bond found in alkyne compound.
Answer: -2.373 x 10^-24J/K(particles
Explanation: Entropy is defined as the degree of randomness of a system which is a function of the state of a system and depends on the number of the random microstates present.
The entropy change for a particle in a system depends on the initial and final states of a system and is given by Boltzmann equation as
S = k ln(W) .
where S =Entropy
K IS Boltzmann constant ==1.38 x 10 ^-23J/K
W is the number of microstates available to the system.
The change in entropy is given as
S2 -S1 = kln W2 - klnW1
dS = k ln (W2/W1)
where w1 and w2 are initial and final microstates
from the question, W2(final) = 0.842 x W1(initial), so:
= 1.38*10-23 ln (0.842)
=1.38*10-23 x -0.1719
= -2.373 x 10^-24J/K(particles)
