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3 years ago

Basalt with half live of 10 million years and 1/8 is remaining, how old is rock?

1 answer:

6 0

You multiply 1/8 by 10,000,000 = 1,250,000

we know 3 half life makes 1/8

1/2*1/2*1/2 = 1/8 . 3 half lifes.

3 * 1,250,000 = 3,750,000

You might be interested in

Considering radiation weighting factors only, how many times more dangerous are alpha particles than protons?

alina1380 [7]

Answer:

C. 10

Explanation:

So wr for protons is 2 and wr for alpha particles is 20. In these terms, alpha particles cause ten times more damage then protons.

6 0

2 years ago

Read 2 more answers

Enter your answer in the provided box. Calculate the volume of a 1.420 M NaOH solution required to titrate 40.50 mL of a 1.500 M

Nikolay [14]

Explanation:

Below is an attachment containing the solution.

7 0

2 years ago

A 2.20 mol sample of NO 2 ( g ) is added to a 3.50 L vessel and heated to 500 K. N 2 O 4 ( g ) − ⇀ ↽ − 2 NO 2 ( g ) K c = 0.513

igor_vitrenko [27]

Answer:

[NO₂] = 0.434 M

[N₂O₄] = 0.0971 M

Explanation:

The equilibrum is: N₂O₄(g) ⇆ 2NO₂ (g)

1 moles of nitrogen (IV) oxide is in equilibrium with 2 moles of nitrogen dioxide.

Initally we only have 2.20 moles of NO₂. So let's write the equilibrium again:

2NO₂ (g) ⇆ N₂O₄(g)

Initially 2.20 mol -

React x x/2

X amount has reacted, and the half has been formed, according to stoichiometry.

Eq (2.20-x) / 3.50L (x/2)/ 3.50L

We divide by the volume because we need molar concentrations. Let's make the Kc's expression:

Kc = [N₂O₄] / [NO₂]²

0.513 = ((x/2)/ 3.50L) / [(2.20-x) / 3.50L]

0.513 = ((x/2)/ 3.50L) / [(2.20-x)² / 3.50L²]

0.513 = ((x/2)/ 3.50L) / [2.20-x)² / 3.50L²]

0.513 = ((x/2)/ 3.50L) / (4.84 - 4.40x + x²) / 12.25)

0.513 / 12.25 (4.84 - 4.40x + x²) = x/2 / 3.50

0.203 - 0.184x + 0.0419x² = x/2 / 3.50

3.50(0.203 - 0.184x + 0.0419x²) = x/2

7 (0.203 - 0.184x + 0.0419x²) - x = 0

1.421 - 2.288x + 0.2933x² = 0 → Quadratic formula

a = 0.2933 ; b = -2.288 ; c = 1.421

(-b +- √(b²-4ac)) / (2a)

x₁ = 7.12

x₂ = 0.68 → We consider this value, so we can have a (+) concentration.

Concentrations in the equilibrium are:

[NO₂] = (2.20-0.68) / 3.50 = 0.434 M

[N₂O₄] = (0.68/2) / 3.50 = 0.0971 M

8 0

2 years ago

Which ligand binds tightest? ligand A, with a dissociation constant ( Kd ) of 10−9 M ligand D, with a percent occupancy of 80% a

Delvig [45]

Answer:

The answer will be Ligand A with a dissociation constant (Kd) of $10^{-9}$ M

Explanation:

When the dissociation constant in the ligand is small (in order of nano) ( $10^{-9}$ ) it will be more tied. Due to a dissociation constant measures how much a ligand can be able to be separated from the protein so if the number is small it means that the ligand is highly binded to the protein.

On the other hand, the occupancy percentage of the ligand does not imply binding. Conversely, a High-affinity ligand binding with the proteins implies that a relatively low concentration of a ligand is adequate to occupy the maximum ligand-binding site.

6 0

2 years ago

What are cells at express the same gene

Dafna1 [17]

Hi There!

Question - What are cells at express the same gene?

Answer - A. the same

Why - Every single cell in a person body has the exact same DNA.

Hope This Helps :)

6 0

3 years ago