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2 years ago

You discover some bones that have roughly %s as much carbon-14 in them as

Chemistry

2 answers:

Misha Larkins [42]2 years ago

7 0

Answer:

If a fossil bone is found to contain 1/8th as much Carbon-14 as the bone of a living animal, what is the approximate age of the fossil?(half-life of C-14 = 5800 years)

Explanation:

Dafna1 [17]2 years ago

4 0

Answer:

150 years i guess so? im nkt sure

You might be interested in

Which objects are malleable tin fork and knife from a camping set, antique ceramic case, steel pole fence post, marble sculpture

LenaWriter [7]

Answer:

Tin fork and knife from a camping set, a steel pole fence post, and a copper coin.

Explanation:

Hope this halps. UwUz

7 0

2 years ago

What mass of H₂O is formed when excess H₂ reacts with 64 g of O₂

taurus [48]

Answer: 72 g of $H_2O$ is formed.

Explanation:

To calculate the moles :

$\text{Moles of solute}=\frac{\text{given mass}}{\text{Molar Mass}}$

$\text{Moles of} O_2=\frac{64}{32}=2moles$

$2H_2+O_2(g)\rightarrow 2H_2O$

As $H_2$ is the excess reagent, $O_2$ is the limiting reagent as it limits the formation of product.

According to stoichiometry :

1 mole of $O_2$ produce= 2 moles of $H_2O$

Thus 2 moles of $O_2$ will require= $\frac{2}{1}\times 2=4moles$ of $H_2O$

Mass of $H_2O=moles\times {\text {Molar mass}}=4moles\times 18g/mol=72g$

Thus 72 g of $H_2O$ is formed.

4 0

2 years ago

(07.07 MC) Consider the following equilibrium reaction having gaseous reactants and products. 4HCl + O2 ⇌ 2H2O + Cl2 Which of th

DochEvi [55]

Answer: b. the volume of water vapour increases

Explanation:

when there's an increase in concentration, the equilibrium favours the forward reaction, more product is produced, froward reaction is faster

3 0

2 years ago

How many moles of HCl are needed to completely react with 50.0 mL of 0.250 M NaOH solution? Group of answer choices 1.25 × 10-2

Hitman42 [59]

Answer:

$n_{HCl|=1.25\times 10^{-2}\ moles$

Explanation:

We know that , the reaction between NaOH and HCl is given as

$HCL+NaOH\rightarrow NaCl+H_2O$

Form the above reaction we can say that

Number of moles of HCl =Number of moles of NaOH

$n_{HCl} =n_{NaOH}$

Therefore

$n_{HCl}=\frac{0.25\times 50}{1000}\ moles$

$n_{HCl|=12.5\times 10^{-3}\ moles$

$n_{HCl|=1.25\times 10^{-2}\ moles$

Therefore the numbers of moles needed of HCl wil be $1.25\times 10^{-2}\ moles$

6 0

2 years ago

A new sunscreen has been developed that is supposed to be more effective at preventing sunburn. 30 participants spray one arm wi

faltersainse [42]

Answer:

Explanation:

This question appears incomplete but can however still b answered.

The purpose of the experiment is to test the effectiveness of the new sunscreen.

An independent variable is the variable that is changed (directly or indirectly) during the course of an experiment. The independent variable here are the sunscreen.

A dependent variable is the variable that is been tested in the course of the experiment. The dependent variable here is the redness of the skin.

The first group here (this could be in the missing part of the question, hence response not certain) is the control group. The control group consists of the arms sprayed with the leading/old sunscreen formula.

The second group is the test group. It consists of the arms sprayed with the new sunscreen formula.

The factors that are kept constant (or control variable) are the duration under the sun (4 hrs) and the participants' arms used.

The test group is the second group while the group used for comparison (to be sure the new sunscreen is more effective) is the first group.

8 0

2 years ago