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
ella [17]
1 year ago
8

What is the mass of 0.257 mol of calcium nitrate?

Chemistry
1 answer:
poizon [28]1 year ago
4 0

Answer: 42.14 g

Explanation:      calcium nitrate -  Ca(NO_{3} )_{2}

                   , the molar mass of calcium nitrate = 164 g

<h3>                   formula used = given mass/molar mass= no of moles </h3>

                   mass required =0.257*164

                                               =42.14 g

                     

             

You might be interested in
One radioactive isotope of calcium has an atomic mass of 47,how many neutrons are in the calcium -47 nucleus
jekas [21]

Answer: 27 neutrons

Explanation:

Recall that the number of protons in the nucleus of an atom = Atomic number.

Hence, Calcium with mass number 47 and atomic number 20 will have 20 protons

Therefore, since Mass number = number of protons + neutrons

47 = 20 + neutrons

Neutrons = 47 - 20 = 27

Thus, there are 27 neutrons in radioactive calcium nucleus.

6 0
3 years ago
Extend your thinking: The slow decay of radioactive materials can be used to find the age of rocks, fossils, and archaeological
lisov135 [29]

The age in years of the Egyptian papyrus, the Aboriginal charcoal, the Mayan headdress, and the Neanderthal skull are 4000 years, 13106.5years , 2040 years, and 30353 years respectively.

<h3>What is the half-life of a radioactive material?</h3>

The half-life of a radioactive material is the time taken for half the atoms present in the material to decay or disintegrate.

The half-life, t_\frac{1}{2}, the age, t, and amount remaining, A_{r}, of a radioactive material are related by the formula below:

  • t = \frac{t_\frac{1}{2}*A_{r}}{-ln2}

Half-life of carbon-14 = 6000 years

For the Egyptian papyrus with 63% of its original carbon-14 atoms:t = \frac{6000*0.63}{-0.63} = 4000\:years

For the Aboriginal charcoal with 22% of its original carbon-14 atoms:

t = \frac{6000*0.22}{-0.63} = 13106.5\:years

For the Mayan headdress with 79% of its original carbon-14 atoms:

t = \frac{6000*0.79}{-0.63} = 2040\:years

Neanderthal skull with 3% of its original carbon-14 atoms:

t = \frac{6000*0.03}{-0.63} = 30353\:years

Therefore, the age in years of the Egyptian papyrus, the Aboriginal charcoal, the Mayan headdress, and the Neanderthal skull are 4000 years, 13106.5years , 2040 years, and 30353 years respectively.

Learn more about half-life at: brainly.com/question/26689704

#SPJ1

6 0
2 years ago
BRAINLIESTTT ASAP!!!! PLEASE HELP ME :)
Elan Coil [88]

Answer:

1s² 2s²2p³  

Explanation:

If the atom has seven electrons, it is Element 7 (nitrogen).

In the Periodic Table, you count the electrons in all the subshells up to

No. 7.

In the first Period, you have filled the 1s level (2 electrons).

In the second Period, you have filled the 2s subshell (2 electrons) and put three electrons in the 2p subshell.

Thus, the electron configuration is

1s² 2s²2p³

Note how the superscripts tell you the number of electrons in each subshell: <em>2 + 2 + 3 = 7</em>.

6 0
3 years ago
If a substance has a half life of 58 years and starts with 500 g radioactive, how much remains radioactive after 30 years?
Vilka [71]

Answer:

A = 349 g.

Explanation:

Hello there!

In this case, since the radioactive decay kinetic model is based on the first-order kinetics whose integrated rate law is:

A=Ao*exp(-kt)

We can firstly calculate the rate constant given the half-life as shown below:

k=\frac{ln(2)}{t_{1/2}} =\frac{ln(2)}{58year}=0.012year^{-1}

Therefore, we can next plug in the rate constant, elapsed time and initial mass of the radioactive to obtain:

A=500g*exp(-0.012year^{-1} *30year)\\\\A=349g

Regards!

5 0
3 years ago
An organic compound is composed of 38.7% C, 9.70% H, 51.6% O. The compound has a molecular formula mass of 62.0g/mol.
Tcecarenko [31]

<span>B)<span>C2H6O<span>2
</span></span></span>
First, convert each percentage to grams: 38.7g, 9.70g, and 51.6g. 
Next, calculate the number of moles of each element, based on the number of grams given.
C = 3.23 mol
H = 8.91 mol
O = 3.23 mol
Set up the ratio of moles of each element:
C3.34H9.70O3.23. Convert the decimals to whole numbers by dividing by the smallest subscript, 3.23.
The empirical formula is CH3O.
Now, compute the formula mass, which is 31. Finally, divide the molecular mass by the formula mass, 62/31 = 2. Multiple the subscripts by 2 to get the molecular formula.
5 0
3 years ago
Read 2 more answers
Other questions:
  • Formula of diamond silver chloride?
    14·1 answer
  • 1. Directions: Select each correct answer.
    5·2 answers
  • Newton's Third Law: "For every action, there is an equal and opposite reaction." ... The forces are the result of
    15·1 answer
  • When hydrochloric acid reacts with sodium sulfide, hydrogen sulfide gas and sodium chloride are produced. How many moles of H2S
    6·1 answer
  • What is the mass, in grams, of 1.26 mol of water, H2O?
    8·1 answer
  • Iron(II) can be oxidized by an acidic K2Cr2O7 solution according to the net ionic equation: Cr2O72− + 6Fe2+ + 14H+ → 2Cr3+ + 6Fe
    12·1 answer
  • In 1803, the British chemist John Dalton proposed several atomic theories. Which one of his theories was later shown to be incor
    8·1 answer
  • What happens when copper sulphate reacts with hydrogen<br>sulphide?​
    12·2 answers
  • 1.
    15·1 answer
  • What are the correct two steps, in the correct order, that would allow you to solve for x in the following equation?
    15·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!