1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
nalin [4]
3 years ago
15

Carbon-14 is used to date previously living matter—either plant or animal. It has a half-life of 5,730 years. A plant fossil was

found to contain 1.75 grams of carbon-14. How long ago did the bone contain 7 grams of carbon-14?
Chemistry
1 answer:
Scilla [17]3 years ago
6 0

Answer:

THE PLANT FOSSIL IS 11, 460 years AT A MASS OF 7 GRAMS.

Explanation:

The half life t1/2 of a radioisotope is the rate of decay of the radioisotope. It is the time taken for half of the total number of atoms in a given sample of an element to decay.

From the question, the half life is 5730 years.

Lets take the original mass of the radioactive substance as 7 grams

the final mass of the substance to be 1.75 grams

The number of half life to decay from 7 g to 1.75 grams would be;

7 grams ----------> 3.5 grams ---------> 1.75 grams

2 half life can be deducted as 7 grams decay to remain 1.75 grams.

To calculate the age of the substance, we multiply the half life by the number of decay it undergoes to remain the final mass.

How old = Half life * number of decay

How old = 5730 * 2

How old = 11,460 years.

The fossil will be 11,460 years at 7 grams before decaying.

You might be interested in
The mass of solute per 100 mL of solution is abbreviated as (m/v). Mass is not technically the same thing as weight, but the abb
Nimfa-mama [501]

Answer:

\boxed{\text{254 g}}

Explanation:

\begin{array}{rcl}\text{\% m/V} & = & \dfrac{\text{Mass of sucrose}}{\text{Volume of solution}}\\\\\text{Let m}& = &\text{mass of sucrose}\\\dfrac{\text{35.0 g}}{\text{100 mL}}& = & \dfrac{m}{\text{725 mL}}\\\\m & = &\dfrac{\text{35.0 g}\times 725}{100}\\\\ & = &\textbf{254 g}\\\end{array}\\\text{You need $\boxed{\textbf{254 g}}$ of sucrose}

3 0
3 years ago
The reaction of hydrogen gas and iron oxide is described by the chemical equation below. 3H2+Fe2O3→2Fe+3H2O How many moles of ir
ELEN [110]

Answer:

2.2 moles of Fe will be produced

Explanation:

Step 1: Data given

Number of moles of hydrogen gas = 3.3 moles

Number of moles of iron oxide = 1.5 moles

Step 2: The balanced equation

3H2 + Fe2O3 → 2Fe + 3H2O

Step 3: Calculate the limiting reactant

For 3 moles H2 we need 1 mol Fe2O3 to produce 2 moles Fe and 3 moles H2O

Hydrogen gas is the limiting reactant. It will completely be consumed (3.3 moles). Fe2O3 is in excess. There will react 3.3 / 3 = 1.1 moles

There will remain 1.5 - 1.1 = 0.4 moles Fe2O3

Step 4: Calculate moles Fe

For 3 moles H2 we need 1 mol Fe2O3 to produce 2 moles Fe and 3 moles H2O

For 3.3 moles H2 we'll have 2/3 * 3.3 = 2.2 moles Fe

2.2 moles of Fe will be produced

5 0
3 years ago
If iodine-131 has a half-life of 8 days, how much of a 64.0 g sample of iodine-131 will remain after 32 day?
Mariulka [41]

Answer:

4 g OF IODINE-131 WILL REMAIN AFTER 32 DAYS.

Explanation:

Half life (t1/2) = 8 days

Original mass (No) = 64 g

Elapsed time (t) = 32 days

Mass remaining (Nt) = ?

Using the half life equation we can obtain the mass remaining (Nt)

Nt = No (1/2) ^t/t1/2

Substituting the values, we have;

Nt = 64 * ( 1/2 ) ^32/8

Nt = 64 * (1/2) ^4

Nt = 64 * 0.0625

Nt = 4 g

So therefore, 4 g of the iodine-131 sample will remain after 32 days with its half life of 8 days.

8 0
3 years ago
Calculate the number of sodium ions, perchlorate ions, Cl atoms and O atoms in 17.8 g of sodium perchlorate. Enter your answers
Degger [83]

17.8 g of sodium perchlorate contains 8.73 × 10²² Na⁺ ions, 8.73 × 10²² ClO₄⁻ ions, 8.73 × 10²² Cl atoms and 3.49 × 10²³ O atoms.

First, we will convert 17.8 g of NaClO₄ to moles using its molar mass (122.44 g/mol).

17.8 g \times \frac{1mol}{122.44g} = 0.145 mol

Next, we will convert 0.145 moles to molecules of NaClO₄ using Avogadro's number; there are 6.02 × 10²³ molecules in 1 mole of molecules.

0.145 mol \times \frac{6.02 \times 10^{23}molecules  }{mol} = 8.73 \times 10^{22}molecules

NaClO₄ is a strong electrolyte that dissociates according to the following equation.

NaClO₄ ⇒ Na⁺ + ClO₄⁻

The molar ratio of NaClO₄ to Na⁺ is 1:1. The number of Na⁺ in 8.73 × 10²² molecules of NaClO₄ is:

8.73 \times 10^{22}moleculeNaClO_4 \times \frac{1 ion Na^{+} }{1moleculeNaClO_4} = 8.73 \times 10^{22}ion Na^{+}

The molar ratio of NaClO₄ to ClO₄⁻ is 1:1. The number of ClO₄⁻ in 8.73 × 10²² molecules of NaClO₄ is:

8.73 \times 10^{22}moleculeNaClO_4 \times \frac{1 ion ClO_4^{-} }{1moleculeNaClO_4} = 8.73 \times 10^{22}ion ClO_4^{-}

The molar ratio of ClO₄⁻ to Cl is 1:1. The number of Cl in 8.73 × 10²² ions of ClO₄⁻ is:

8.73 \times 10^{22}ion ClO_4^{-} \times \frac{1 atomCl }{1ion ClO_4^{-}} = 8.73 \times 10^{22}atom Cl

The molar ratio of ClO₄⁻ to O is 1:1. The number of O in 8.73 × 10²² ions of ClO₄⁻ is:

8.73 \times 10^{22}ion ClO_4^{-} \times \frac{4 atomO }{1ion ClO_4^{-}} = 3.49 \times 10^{23}atom O

17.8 g of sodium perchlorate contains 8.73 × 10²² Na⁺ ions, 8.73 × 10²² ClO₄⁻ ions, 8.73 × 10²² Cl atoms and 3.49 × 10²³ O atoms.

You can learn more Avogadro's number here: brainly.com/question/13302703

8 0
2 years ago
What is Keg for the reaction 2502(g) + O2(g) = 2803(g)?
rewona [7]

Answer:

according to the law of circumference and the perpendicular area of a circle the answer would be c

Explanation:

4 0
3 years ago
Other questions:
  • A client takes 30 ml of magnesium hydroxide and aluminum hydroxide with simethicone P.O. 1 hour and 3 hours after each meal and
    9·1 answer
  • What is the average salinity of ocean water?
    6·2 answers
  • 5.15 Carbon steel (AISI 1010) shafts of 0.1-m diameter are heat treated in a gas-fired furnace whose gases are at 1200 K and pro
    12·1 answer
  • For the reaction 2Fe + O2 = 2FeO, how many grams of iron oxide are produced from 8.00 mol of iron? when o2 is an excess
    8·1 answer
  • Which of the following is not an example of a chemical change?
    7·2 answers
  • PLEASE HELP<br> Why do atoms form bonds with other atoms? Provide example using octet rule
    5·1 answer
  • StitchXpika plzzzzzzzzz
    15·1 answer
  • What is the chemistry​
    7·2 answers
  • The substance being dissolved<br><br> A) Solute<br> B) Solubility<br> C) Solvent
    11·1 answer
  • A molecule has an empirical formula of ch, and its molar mass is known to be 26 g/mol. What is its molecular formula?.
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!