All categories

3 years ago

Which statement about the half-life of a radioactive sample is true?

Chemistry

2 answers:

Sveta_85 [38]3 years ago

8 0

Answer:

B. It measures the tendency of a radioisotope to decay radioactively.

Explanation:

Chem Hnrs EDGE 2021

yanalaym [24]3 years ago

6 0

Answer:

The correct answer is - B. It measures the tendency of a radioisotope to decay radioactively.

Explanation:

The half-life of the radioactive sample is the time it takes to decay to its half amount of the unstable nuclei of its initial amount. It is radioactively decays to its half value or in simple words, it takes the time to decay an unstable nuclei to decay to its half value.

It can take milliseconds to million years to disintegrate the different unstable nuclei of a radioactive substance to disintegrate its half amount to a stable substance.

You might be interested in

Consider the nuclear equation below. 15/8 O ==> 15/7 N + 0/+1 e Which correctly identifies the type of reaction?

sweet [91]

B: Beta plus Decay :)

6 0

3 years ago

A 0.211 g sample of carbon dioxide, CO2, has a volume of 560 mL and a pressure of 429 mmHg whats the temperature of the gas in K

SCORPION-xisa [38]

The temperature of the gas sample is 813 K.

<u>Explanation:</u>

We have to use the ideal gas equation to find the temperature of the gas sample.

The ideal gas equation is PV = nRT

Pressure, P = 429 mm Hg = 0.56 atm

Volume, V = 560 mL = 0.56 L

R = gas constant = 0.08205 L atm mol⁻¹K⁻¹

Mass = 0.211 g

Molar mass of carbon di oxide = 44.01 g / mol

Moles, n = $$\frac{given mass}{molar mass} = \frac{0.211 g}{44.01 g/mol}$

= 0.0047 mol

Now, we have to plugin the above values in the above equation, we will get the temperature as,

$$T= \frac{PV}{nR}$

T = $$\frac{0.56 \times 0.56}{0.08205 \times 0.0047}$

= 813 K

So the temperature of the gas sample is 813 K.

5 0

4 years ago

A cup of coffee (140g) cools from 75°C down to comfortable room temperature 20°C. How much energy does it release to the surroun

Thepotemich [5.8K]

Given that the mass of coffee in the cup = 140 g

Final temperature = $20^{0}C$

Initial temperature = $75^{0}C$

Let us assume the specific heat of coffee is equal to that of water = 4.184 $\frac{J}{g^{0}C }$

Temperature change = T(final) - T(initial) = (20 - 75 ) $^{0}C$

=- 55 $^{0}C$

-Heat given out by coffee = heat absorbed by the surroundings

Heat released into the surroundings =-( $mC(T_{final}-T_{initial})$ )

= $-(140g)4.184\frac{J}{g^{0}C }( -55^{0}C)$

= 32,217 J

4 0

4 years ago

What is the balanced net ionic equation when aqueous solutions of Pb(NO3)2 and KBr are mixed and form a product

Mila [183]

Answer:

KBr+Pb(NO3)2=? is an equation you can use.

Explanation:

8 0

3 years ago

Describe how scientists use models to make predictions.

Rashid [163]

Models help scientists to make predictions about complex systems. Some models are something that you can see or touch. ... Climate models can predict how climate will change as certain gases are added to the atmosphere. To test how good a model is, scientists might start a test run at a time in the past.

6 0

3 years ago

Read 2 more answers