1/2=5750 years, 1/2(1/2)=1/4, (1/2)(1/2)(1/2)=1/8, (1/2)(1/2)(1/2)(1/2)=1/6
4 halflives have passed so 4(5750)=23000 years since the tree was chopped down
1000000 atoms (1/2)=500000 atoms(1/2)=250000(1/2)=125000(1/2)=62500 atoms would remain in the wood after 4 halflives
Dinosaurs became extinct around 62 million years ago, so if 14C's half life has a value of 5750 years, it would be gone or in such small amounts that dating would be ineffective today.
As Potassium decays into Argon in 1.3 billion years, apart from volcanic activity, it would enable geologists to effectively date things that are really, really, really old.
To get the value of ΔG we need to get first the value of ΔG°:
when ΔG° = - R*T*㏑K
when R is constant in KJ = 0.00831 KJ
T is the temperature in Kelvin = 25+273 = 298 K
and K is the equilibrium constant = 4.5 x 10^-4
so by substitution:
∴ ΔG° = - 0.00831 * 298 K * ㏑4.5 x 10^-4
= -19 KJ
then, we can now get the value of ΔG when:
ΔG = ΔG° - RT*㏑[HNO2]/[H+][NO2]
when ΔG° = -19 KJ
and R is constant in KJ = 0.00831
and T is the temperature in Kelvin = 298 K
and [HNO2] = 0.21 m & [H+] = 5.9 x 10^-2 & [NO2-] = 6.3 x 10^-4 m
so, by substitution:
ΔG = -19 KJ - 0.00831 * 298K* ㏑(0.21/5.9x10^-2*6.3 x10^-4 )
= -40
Answer:
i would say 10, so the anser is A.
Explanation:
because there are the same number of protons and electrons, therefore for a regular O, you are supposed to have only 8 protons, but it is charged, thus, whatever the charge is will be taken into consideration into how much the proton and electron doe it have. Thus, for this case, it has 10, because the charge is negative and you have 8 electron plus 2 = 10.
Answer:
B. A reaction at equilibrium will respond to balance a change.
Explanation:
The Le Chatelier's principle states that a reaction will respond to balance a change. This is true for a reaction in chemical equilibrium.
Le Chatelier's principle sates that "if any conditions of a system in equilibrium is changed, the system will adjust itself in order to annul the effect of the change".
- It explains the effect of applying stress on any system in equilibrium.
- The changing conditions are usually concentration, temperature and pressure.
- If the stress due to any of them is applied to a system in equilibrium, the equilibrium will respond in the directions which counteracts the effect of the stress.
The balanced chemical reaction is:
<span>2SO2 + O2=2SO3
</span>
We are given the amounts of the reactants to be consumed in the reaction. These amounts are the starting point for the calculations.
5.0 L SO2 ( 1 mol / 22.4 L ) = 0.2232 mol SO2
3.0 L O2 <span> ( 1 mol / 22.4 L ) = 0.1339 mol O2
From the chemical reaction, the mole ratio of the reactants 2:1. Therefore, the limiting reactant is SO2.
</span><span>0.2232 mol SO2 ( 1 mol SO3 / 2 mol SO2) ( 22.4 L / 1 mol ) = 2.4998 L SO3</span>
