How to solve 3x-2y=4

Modeling Radioactive Decay In Exercise, complete the table for each radioactive isotope.

Travka [436]

Answer :

The amount after 1000 years will be, 5.19 grams.

The amount after 10000 years will be, 0.105 grams.

Step-by-step explanation :

Half-life = 1599 years

First we have to calculate the rate constant, we use the formula :

$k=\frac{0.693}{t_{1/2}}$

$k=\frac{0.693}{1599\text{ years}}$

$k=4.33\times 10^{-4}\text{ years}^{-1}$

Now we have to calculate the amount after 1000 years.

Expression for rate law for first order kinetics is given by:

$t=\frac{2.303}{k}\log\frac{a}{a-x}$

where,

k = rate constant = $4.33\times 10^{-4}\text{ years}^{-1}$

t = time passed by the sample = 1000 years

a = initial amount of the reactant = 8 g

a - x = amount left after decay process = ?

Now put all the given values in above equation, we get

$1000=\frac{2.303}{4.33\times 10^{-4}}\log\frac{8}{a-x}$

$a-x=5.19g$

Thus, the amount after 1000 years will be, 5.19 grams.

Now we have to calculate the amount after 10000 years.

Expression for rate law for first order kinetics is given by:

$t=\frac{2.303}{k}\log\frac{a}{a-x}$

where,

k = rate constant = $4.33\times 10^{-4}\text{ years}^{-1}$

t = time passed by the sample = 10000 years

a = initial amount of the reactant = 8 g

a - x = amount left after decay process = ?

Now put all the given values in above equation, we get

$10000=\frac{2.303}{4.33\times 10^{-4}}\log\frac{8}{a-x}$

$a-x=0.105g$

Thus, the amount after 10000 years will be, 0.105 grams.

4 0

3 years ago

if You flip an coin 200 times about how many times would you expect the coin to labd on tails what is the probality

harkovskaia [24]

Answer:

50% or 1/2

Step-by-step explanation:

The chance of a coin landing on tails is always 50/50

6 0

3 years ago

a collection of dimes and quarters is worth $19.85. There are 128 coins in all. How many of each type of coin are in the collect

PolarNik [594]

Number of dimes were 81 and number of quarters were 47

Solution:

Let "d" be the number of dimes

Let "q" be the number of quarters

We know that,

value of 1 dime = $ 0.10

value of 1 quarter = $ 0.25

Given that There are 128 coins in all

number of dimes + number of quarters = 128

d + q = 128 ------ eqn 1

Also given that collection of dimes and quarters is worth $19.85

number of dimes x value of 1 dime + number of quarters x value of 1 quarter = 19.85

$d \times 0.10 + q \times 0.25 = 19.85$

0.1d + 0.25q = 19.85 -------- eqn 2

Let us solve eqn 1 and eqn 2

From eqn 1,

d = 128 - q -------- eqn 3

Substitute eqn 3 in eqn 2

0.1(128 - q) + 0.25q = 19.85

12.8 - 0.1q + 0.25q = 19.85

12.8 + 0.15q = 19.85

0.15q = 7.05

Therefore from eqn 3,

d = 128 - q

d = 128 - 47

Thus number of dimes were 81 and number of quarters were 47

4 0

3 years ago

A pizza shop sells pizzas for $7.50 each plus $1.25 per topping. The total price of the pizza can be determined by the

drek231 [11]

The range is (10,11.5,12.5,13.75)
Enjoy your day, mi amor! ❤️

7 0

3 years ago

There are 10soccer teams in the S-league. Each team plays one match against each of the other teams. How many matches will be pl

ipn [44]

1 - 2 - 3 - 4 - 5 - 6 - 7 - 8 - 9 - 10 are your team numbers
1 - 2
1 - 3
1 - 4
1 - 5
1 - 6
1 - 7
1 - 8
1 - 9
1 - 10
2 - 3
2 - 4
2 - 5
2 - 6
2 - 7
2 - 8
2 - 9
2 - 10
3 - 4
3 - 5
3 - 6
3 - 7
3 - 8
3 - 9
3 - 10
4 - 5
4 - 6
4 - 7
4 - 8
4 - 9
4 - 10
5 - 6
5 - 7
5 - 8
5 - 9
5 - 10
6 - 7
6 - 8
6 - 9
6 - 10
7 - 8
7 - 9
7 - 10
8 - 9
8 - 10
9 - 10

45 matches in all >.< :)

8 0

3 years ago