Answer:
39.13
Explanation:
To find that atomic mass of this potassium, we follow the steps below:
Given parameters:
Abundance of K - 39 = 93.26%
Mass of K - 39 = 39
Abundance of K - 41 = 6.73%
Mass of K - 41 = 41
To find the average atomic mass;
Average atomic mass =( mass x abundance of k -39 ) +( mass abundance of k- 41)
Average atomic mass = (39 x 93.26%) + (41 x6.73% ) = 39.13
Elements that tend to gain electrons to form anions during chemical reactions are called non-metals. These are electronegative elements with high ionization energies. They are non-lustrous, brittle and poor conductors of heat and electricity (except graphite).
biochemist isolates, purifies, and combines in a test tube a variety of molecules needed for dna replication. when she adds some dna to the mixture,replication occurs, but each dna molecule consists of a normal strand paired with numerous segments of dna a few hundred nucleotides long.
she probably has left out DNA ligase of the mixture
It is about 6 x 10^23. So in 5 moles of oxygen gas, which has a mass of 5x16=80 grams, there are 5x6x10^23 = 30x10^23 molecules.
Amount of CH4 is excess, so no need to worry about it
<span>but the limiting factor is the Oxygen </span>
<span>according to stranded equation, </span>
<span>CH4 + 2 O2 --> CO2 + 2 H2O ΔH = -889 kJ/mol </span>
<span>just by taking proportions </span>
<span>(-889 kJ/mol) / 2 x 0.8 mol = - 355.6 kJ </span>
<span>so i think the answer is (a)</span>
