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3 years ago

3.

Chemistry

1 answer:

Katena32 [7]3 years ago

6 0

Answer:

it's A endothermic its when two objects rub each other to form heat this is also known as friction force

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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

How many atoms, ions, or molecules are in a 1 molar solution?

Nezavi [6.7K]

Molarity refers to moles/ L. This indicates the concentration of a solution containing solute and solvent.

1 molar solution contains 1 mole of solute in 1 L of solvent.

According to Avogadro's number, 1 mole of a substance contains 6.023 x 10^23 molecules, atoms, or ions.

For this reason, 6.023 x 10^23 atoms, ions, or molecules are in a molar solution.

7 0

3 years ago

In order to predict the outcome of the reaction, write the molecular, full ionic, and net ionic equations for a mixture of aqueo

Elina [12.6K]

Answer:

See explanation

Explanation:

Full molecular equation;

2NH3(aq) + AgNO3(aq) -------> [Ag(NH3)2]NO3(aq)

Full ionic equation

2NH3(aq) + Ag^+(aq) + NO3^-(aq) --------> [Ag(NH3)2]^+(aq) + NO3^-(aq)

Net ionic equation;

2NH3(aq) + Ag^+(aq) --------> [Ag(NH3)2]^+(aq)

When Silver nitrate is mixed with a solution of aqueous ammonia, a white and cloudy solution was observed.

6 0

3 years ago

How did music change during medieval, renaissance and baroque eras

Vilka [71]

Answer:

usage of trills and vibrato

Explanation:

earlier music used trills while later styles would use vibrato.

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3 years ago

Minerals are _________ inorganic _________ that usually possess a crystalline structure and can be represented by a chemical for

ladessa [460]

Answer:

The corect answer is c) naturally occurring; solids

Explanation:

Minerals exists as solid substances in nature consisting of one or more element chemically combined together formiming compounds with definite composition. As mentioned earlier single elements can form minerals and examples of single element mineral are Silver, Carbon and Gold which are found in nature in their pure form and are mined.

Minerals are normally found in rocks, which may contain one ore more different types of minerals

7 0

3 years ago