Answer:
the second one looks like it so I picked the second one
H2O is the chemical formula of water. It means that each molecule of water is made up of two hydrogen atoms, indicated by the letter H, and a single oxygen atom, represented by the O. Water is a chemical substance with no smell, taste, or color.
Answer:
a) the atomic number is 15
b) the mass number is 15+16 = 31
c) element is phosphorus
d)Group 15 period 3
Answer:
<em>One mole of anything is 6.022×1023 everythings, including atoms. Multiply the moles Fe by 6.022×1023 atoms/mol. 3.77mol Fe ×6.022×1023atoms Fe1mol Fe =2.27×1024 atoms Fe rounded to three significant figures.</em>
The average kinetic energy of an ideal gas is calculated as
KE_avg = 3/2 kT
where T is the temperature in Kelvin and k=R/N_A; R is the universal gas constant and N_A is the number of moles.
Thus, upon substitution we get
KE_avg = 3/2(8.314/1)(100+273)
KE_avg = 3/2(8.314)(373)
KE_avg = 4651.683
The average kinetic energy of 1 mole of a gas at 100 degree Celsius is 4651.683 J.