<u>Answer:</u> The tree was burned 16846.4 years ago to make the ancient charcoal
<u>Explanation:</u>
The equation used to calculate rate constant from given half life for first order kinetics:

where,
= half life of the reaction = 5715 years
Putting values in above equation, we get:

Rate law expression for first order kinetics is given by the equation:
![k=\frac{2.303}{t}\log\frac{[A_o]}{[A]}](https://tex.z-dn.net/?f=k%3D%5Cfrac%7B2.303%7D%7Bt%7D%5Clog%5Cfrac%7B%5BA_o%5D%7D%7B%5BA%5D%7D)
where,
k = rate constant = 
t = time taken for decay process = ? yr
= initial amount of the sample = 100 grams
[A] = amount left after decay process = 13 grams
Putting values in above equation, we get:

Hence, the tree was burned 16846.4 years ago to make the ancient charcoal
Answer:
2.52 g NaCl
Explanation:
(Step 1)
To find the mass, you first need to find the moles NaCl. This value can be found using the molarity ratio:
Molarity = moles / volume (L)
After you convert mL to L, you can plug the given values into the equation and simplify to find moles.
136.9 mL / 1,000 = 0.1369 L
Molarity = moles / volume
0.315 M = moles / 0.1369 L
0.0431 = moles
(Step 2)
Now, you can use the molar mass to convert moles to grams.
Molar Mass (NaCl): 22.990 g/mol + 35.453 g/mol
Molar Mass (NaCl): 58.443 g/mol
0.0431 moles NaCl 58.443 g
------------------------------ x ------------------- = 2.52 g NaCl
1 mole
Answer:
the Bohr model, an electron's position is known precisely because it orbits the nucleus in a fixed path. In the electron cloud model, the electron's position cannot be known precisely. Only its probable location can be known.
Answer:
Sodium is a silvery-white metal that reacts with chlorine gas, which is a yellow-greenish gas that is toxic. The reaction gives off a lot of heat. After the reaction, which statement is true about the chemical properties of the product, sodium chloride?
Pure sodium reacts violently and sometimes explosively with water producing sodium hydroxide, hydrogen gas and heat
2Na(s) + 2H2O(l) → 2NaOH(aq) + H2(g)
Chlorine is a very poisonous yellow green gas with a sharp odour that was used in gas warfare during WW1
Sodium and chlorine reacts with each other, however, to produce one of the most familiar substance used in cooking and preservation industry today Sodium Chloride or Common salt or table salt in the irreversible equation;
2Na(s) + Cl2(g) → 2NaCl(s)
Explanation:
It is easy to see why this reaction takes place so readily sodium has one electron in its outermost valence shell while chlorine has seven electrons in its valence shell. when sodium atom transfers one electron to chlorine atom forming a sodium cation (Na+) and a chloride anion (Cl-) both ions have complete valence shells and are energetically more stable. the reaction is extremely exothermic, producing a bright yellow light and a great deal of heat and fumes of sodium chloride.
In a reaction observation of the reaction process you will see sodium flares up almost immediately upon reaction with water.
You know that you can just google it right? It has this converter.