By studying the fossil record we can tell how long life has existed on Earth, and how different plants and animals are related to each other. Often we can work out how and where they lived, and use this information to find out about ancient environments. Fossils can tell us a lot about the past.
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.
Osmolarity=osmole of the solute/litres of the solution
ionic equation for dissociation of CaCl2 is
CaCl2--->Ca2+ +2Cl-
total osmoles for reaction are 1(Ca2+) + 2(Cl-)= 3 osmoles
therefore
0.50 moles of CaCl2 x 3 osmoles/ 1mole of CaCl2 = 1.5osmoles
osmolarity=1.5 /1.0 L=1.5 osmol/l
Answer:
1.48 M
Explanation:
Step 1:
The balanced equation for the reaction. This is given below:
Mg + H2SO4 —> MgSO4 + H2
Step 2:
Determination of the number of mole of Mg in 80.0 mL of 0.200 M Mg solution. This is illustrated below:
Molarity of Mg = 0.200 M
Volume of solution = 80 mL = 80/1000 = 0.08L
Mole of Mg =?
Molarity = mole /Volume
0.2 = mole /0.08
Mole = 0.2 x 0.08
Mole of Mg = 0.016 mole.
Step 3:
Determination of the number of mole of H2SO4 that reacted. This is illustrated below:
Mg + H2SO4 —> MgSO4 + H2
From the balanced equation above,
1 mole of Mg reacted with 1 mole of H2SO4.
Therefore, 0.016 mole of Mg will also react with 0.016 mole of H2SO4.
Step 4:
Determination of the concentration of the acid.
Mole of H2SO4 = 0.016 mole.
Volume of acid solution = 10.8 mL = 10.8/1000 = 0.0108 L
Molarity =?
Molarity = mole /Volume
Molarity = 0.016/0.0108
Molarity of the acid = 1.48 M
Therefore, the concentration of acid is 1.48 M
Answer is: <span>ch3co2h; acetic acid.
</span><span>An Arrhenius acid is a
substance that dissociates in water to form hydrogen ions or protons.
</span>Acetic acid dissociate in aqueous solution to form hydrogen ions (H⁺) and acetic anion (CH₃COO⁻).
<span>Balanced chemical reaction (dissociation):
CH</span>₃COOH(aq) ⇄ CH₃COO⁻(aq) + H⁺(aq).
