How many atoms are present in a 0.600- mole sample of gold?

Carbon-14 (14C) dating assumes that the carbon dioxide on the Earth today has the same radioactive content as it did centuries a

Nataly [62]

<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:

$t_{1/2}=\frac{0.693}{k}$

where,

$t_{1/2}$ = half life of the reaction = 5715 years

Putting values in above equation, we get:

$k=\frac{0.693}{5715yrs}=1.21\times 10^{-4}yrs^{-1}$

Rate law expression for first order kinetics is given by the equation:

$k=\frac{2.303}{t}\log\frac{[A_o]}{[A]}$

where,

k = rate constant = $1.21\times 10^{-4}yr^{-1}$

t = time taken for decay process = ? yr

$[A_o]$ = initial amount of the sample = 100 grams

[A] = amount left after decay process = 13 grams

Putting values in above equation, we get:

$1.21\times 10^{-4}=\frac{2.303}{t}\log\frac{100}{13}\\\\t=16864.4yrs$

Hence, the tree was burned 16846.4 years ago to make the ancient charcoal

8 0

3 years ago

Torrey's neighbor told her that a marble rolling down a hill increases in velocity as it rolls down, but does not increase in ki

ziro4ka [17]

Answer:

Torrey's neighbour is incorrect because increase in kinetic energy is proportional to velocity. If the velocity increases so will the object's kinetic energy. Because the mass is constant, if the velocity increases, so does the kinetic energy.

6 0

3 years ago

What are to long term impacts that the concept of matter cannot be destroyed or created

Tcecarenko [31]

As long as matter cannot be destroyed or created , nothing can be gained or lost.

there is zero impact and hence one cannot numerate the impact

8 0

3 years ago

How many grams of mercury can be produced if 18.0 g of mercury (11) oxide decomposes?

NARA [144]

Answer:

18.0 g of mercury (11) oxide decomposes to produce 9.0 grams of mercury

Explanation:

Mercury oxide has molar mass of 216.6 g/ mol. It gas a molecular formula of HgO.

The decomposition of mercury oxide is given by the chemical equation below:

2HgO ----> 2Hg + O₂

2 moles of HgO decomposes to produce 1 mole of Hg

2 moles of HgO has a mass of 433.2 g

433.2 g of HgO produces 216.6 g of Hg

18.0 of HgO will produce 18 × 216.6/433.2 g of Hg = 9.0 g of Hg

Therefore, 18.0 g of mercury (11) oxide decomposes to produce 9.0 grams of mercury

3 0

3 years ago

Charles’ Law can be expressed mathematically as V=kT. If the constant k for 6.0 L of gas is 0.020 L/K (liters per kelvin), what

kozerog [31]

Answer: 300 K

Explanation:

Charles' Law: This law states that volume is directly proportional to the temperature of the gas at constant pressure and number of moles.

$V\propto T$ (At constant pressure and number of moles)

$V=kT$

Given : V= 6.0 L

k= 0.020 L/K

T=?

$6.0=0.020LK^{-1}\times T$

$T=300 K$

Thus temperature of the gas is 300 K.

3 0

3 years ago