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
horsena [70]
3 years ago
13

How old is a bone if it now .3125 of C-14 when it originally had 80.0g of C-14

Chemistry
1 answer:
Taya2010 [7]3 years ago
7 0
<h3>Answer:</h3>

42960 years

<h3>Explanation:</h3>

<u>We are given;</u>

  • Remaining mass of C-14 in a bone is 0.3125 g
  • Original mass of C-14 on the bone is 80.0 g
  • Half life of C-14 is 5370 years

We are required to determine the age of the bone;

  • Using the formula;
  • Remaining mass = Original mass × 0.5^n , where n is the number of half lives.

Therefore;

0.3125 g = 80.0 g × 0.5^n

3.90625 × 10^-3 = 0.5^n

  • Introducing logarithm on both sides;

log 3.90625 × 10^-3 = n log 0.5

Solving for n

n = log 3.90625 × 10^-3 ÷ log 0.5

   = 8

  • Therefore, the number of half lives is 8
  • But, 1 half life is 5370 years
  • Therefore;

Age of the rock = 5370 years × 8

                          = 42960 years

Thus, the bone is 42960 years old

You might be interested in
6. The Earth’s electric field is directed vertically downward; at the ground level its strength is E = 130 N/C, and at an altitu
Alexxx [7]

Answer:

5.31x10⁻⁶ C

Explanation:

The cube is located 100 m altitude from the ground, so the superior face is at 100m and has E = 70 N/C, and the inferior face is at the ground with E = 130 N/C.

The electric field is perpendicular to the bottom and the top of the cube, so the total flux is the flux at the superior face plus the flux at the inferior face:

Фtotal = Ф100m + Фground

Where Ф = E*A*cos(α). α is the angle between the area vector and the field (180° at the topo and 0° at the bottom):

Фtotal = E100*A*cos(180°) + Eground*A*cos(0°)

Фtotal = 70A*(-1) + 130*A*1

Фtotal = 60A

By Gauss' Law, the flux is:

Фtotal = q/ε, where q is the charge, and ε is the permittivity constant in vacuum = 8.854x10⁻¹² C²/N.m²

A = 100mx100m = 10000 m²

q = 60*10000*8.854x10⁻¹²

q = 5.31x10⁻⁶ C

8 0
3 years ago
Find the linear function Cequals​f(F) that gives the reading on the Celsius temperature scale corresponding to a reading on the
padilas [110]

Answer:

C = (5/9) F - (160/9)

They both read equal at Z = - 40

Explanation:

We are looking for a linear function so we can write the following condition

Y = aX + b

Applying it to the exercise we got C = a F + b

Let's use the facts that C = 0 when F = 32 and C = 100 when F = 212

0 = 32 a + b            (1)

100 = 212 a + b       (2)

From (1) b = - 32 a , when we replace this in (2) we obtain a = (5/9)

and b = - (5/9)32 = - 160/9

Finally the linear function is C = (5/9) F - (160/9)

Both readings are equal at a Z number so

Z = (5/9) Z - 160/9

(4/9) Z = -160/9 and Z = - 40

6 0
3 years ago
What is a displacement reactions​
Alisiya [41]

<h2><u>Question</u><u>:</u>-</h2>

\textsf{what is a displacement reactions?   }      

<h2><u>Answer</u><u>:</u></h2>

\large \underbrace{ \underline{ \sf Displacement \: reaction}}

The reaction in which more reactive element replace a less reactive element from its compound is called displacement reaction.

Ex:-

\bold{\large Zn+HCl \longrightarrow ZnCl_2+H_2}

6 0
3 years ago
Read 2 more answers
Please help me, I really need it, God Bless you &lt;3
gladu [14]

#1

\\ \sf\longmapsto {}^{88}_{38}Sr^{2+}

  • As 2 electrons are donated Hence the No of electrons =38-2=36

#2

\\ \sf\longmapsto {}^{51}_{23}V^{3+}

  • As 3 electrons donated the no of electrons=23-3=20

#3

\\ \sf\longmapsto {}^{55}_{26}Fe^{3+}

  • No of neutrons=55-26=29

#4

\\ \sf\longmapsto {}^{112}_{48}

  • As 2 electrons are donated no of electrons =48-2=46

#5

\\ \sf\longmapsto {}^{210}_{82}Pb^{2+}

  • No of neutrons=210-82=128
7 0
2 years ago
Which of the following will increase the pitch of a sound?
AnnZ [28]

Answer:

A) increasing tension in the vibrating object.

4 0
3 years ago
Read 2 more answers
Other questions:
  • A catalyst lowers the activation energy for both the forward and the reverse reactions in an equilibrium system, so it has no ef
    6·2 answers
  • PLZ HELP HURRY PLZZZZZ WILL GIVE BRAINLIEST
    12·1 answer
  • What is the frequency of a photon with a wavelength of 1040 nm. Report your answers to three significant digits. The frequency i
    12·1 answer
  • What makes an ionic compound an ionic compound?
    11·1 answer
  • You have a glass of liquid and combine it with a mysterious solid and notice that over time the color changes. this questions ha
    14·1 answer
  • A non polar solute will most likely dissolve in a polar solvent because opposites attract. Select one: True False
    10·1 answer
  • How many molecules are present in a sample of carbon dioxide, CO2 with a mass of 168.2?
    10·1 answer
  • What is the density of an aqueous solution that is 50.0% KOH by mass and has a KOH concentration of 13.39 M?
    5·1 answer
  • Most terrestrial plants are members of this Division:
    10·2 answers
  • Solar power plants convert a form of<br> energy to an<br> form of energy
    10·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!