Answer:
The element argon is in column 8A and is a noble gas. Nobles gases are completely stable because their outershell is filled with all eight electrons. Argon has eight valence electrons.
Answer:
C. element. oxygen is an element
Explanation:
oxygen is element #8
Answer: 404.04 kJ.
Explanation:
To calculate the moles, we use the equation:
moles of 
According to stoichiometry :
2 moles of on burning produces = 1036 kJ
Thus 0.78 moles of on burning produces =
Thus the enthalpy change when burning 26.7 g of hydrogen sulfide is 404.04 kJ.
The density of an object or quantity of matter is its mass divided by its volume.
<span>write out the balance equation
3NaOh+H3PO4->Na3PO4+3H2O
You are given everything needed to calculate
q=heat transfer=2.2*10^2,
H3PO4 moles= 1.5*10^-3,
NaOH moles=5.0*10^-3
equation is deltaHneutraliztion=q/Moles of limiting reagent
H3PO4 is limiting reagent because lowest moles, and is used up first
Now plug in variables
DeltaH=2.2*10^2(1.5*10^3)= 146.67kj/mole
Notice we had to convert J to kj,</span>
