An index fossil is a fossil that is useful for dating and correlating the strata in which it is found.
Or it is a fossil that helps you find the date where it has been found. I rephrased that.
Answer:
0.444 mol/L
Explanation:
First step is to find the number of moles of oxalic acid.
n(oxalic acid) = 
Now use the molar ratio to find how many moles of NaOH would be required to neutralize 
of oxalic acid.
n(oxalic acid): n(potassium hydroxide)
1 : 2 (we get this from the balanced equation)
: x
x = 0.0111 mol
Now to calculate what concentration of KOH that would be in 25 mL of water:
Explanation:
Fe2o3+ 3co ---------. 2fe + 3co2
A chemical compound made up of ions by forces that create ionic bonding. It is a neutral compound.
Answer:
The nuclear charge increases from boron to carbon, but there is no additional shielding( that is no additional shells).
Explanation:
First of all, we must know the electron configuration of carbon and boron.
Boron- 1s2 2s2 2p1
Carbon- 1s2 2s2 2p2
Moving from boron to carbon, the effective nuclear charge increases without a corresponding increase in the number of shells. Remember that shielding increases with increase in the number of intervening shells between the outermost electron and the nucleus. Since there isn't an increase in shells, boron experience a lower screening effect.
From
Zeff= Z- S
The Z for carbon is 6 while for boron is 5 even though both have the same number of screening electron S(4 screening electrons). Hence it is expected the Zeff(effective nuclear charge) for boron will be less than that of carbon.
