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
Natali5045456 [20]
2 years ago
10

What are isotopes?

Chemistry
2 answers:
hodyreva [135]2 years ago
7 0

Answer:

B. ATOMS OF THE SAME ELEMENT THAT HAVE A DIFFERENT NUMBER OF NUETRONS

Explanation:

Each of two or more forms of the same element that contain equal numbers of protons but different numbers of neutrons in their nuclei, and hence differ in relative atomic mass but not in chemical properties; in particular, a radioactive form of an element.

Elis [28]2 years ago
6 0

Answer:

B

Explanation:

You might be interested in
The periodic table is based on an element's
nasty-shy [4]

Answer:

Atomic number

Explanation:

7 0
3 years ago
How many moles are present in a 24.5 gram sample of K2Cr2O7?
attashe74 [19]
The answer to this is solved through stochiometry: the answer is  this: 0.0833mol

6 0
3 years ago
4NH3 (g)+502(g)->6H20g)+4NOg) What is the enthalpy change for this reaction?
Feliz [49]
Enthalpy is energy of bonds broken - energy of bonds formed. Here, the NH3 and O2 are broken and H2O and NO are formed. So the energy to break the NH3 bonds is 3 times the amount of energy it takes to break a N-H single bond (because there are three of them in a NH3 molecule) and then multiplied by 4 because there are four particles.

So the energy of the bonds broken is 12x the energy to break a N-H single bond plus 5x the amount of energy to break an O—O double bond (you don’t multiply this by anything because in each O2 molecule there is only one bond).

The energy of the bonds formed is 6*2 = 12 Times the amount of energy for a O-H single bond plus 4 times the amount of energy required to break a N—O double bond.

Subtract energy of bonds broken - energy of bonds formed and this is the change in enthalpy.

To know what type of bond it is, draw the Lewis structure.
7 0
3 years ago
_A1Br3+_K=_KBr+_A1<br> fill in the correct coefficients.
Nataly_w [17]
1 A1Br3 + 3 K = 3 KBr + 1 A1
3 0
3 years ago
If 0.500 mol neon at 1.00 atm and 273 K expands against a constant external pressure of 0.100 atm until the gas pressure reaches
trapecia [35]

Answer:

The work done on neon = -323 J

The internal energy change= -392.84 J

The heat absorbed by neon = -69.84 J

Explanation:

Step 1: Data given

Number of moles  = 0.500 moles

Pressure  = 1 atm

Temperature  = 273 Kelvin

The pressure will change from 1.00 atm to 0.200 atm. The temperature changes from 273 to 210 Kelvin.

a) calculate the work done on neon

W = -P(V2-V1)    

⇒ with P = the pressure = 0.1 atm

⇒ with V1 = the initial volume = nRTi /Pi

⇒ with V2 = the final volume = nRTf /Pf

W = -PnR((T2/P2) -(T1/P1))

⇒ with T2 = the final temperature = 210 K

 ⇒ with T1 = the initial temperature = 273 K

 ⇒ with P2 = the final pressure = 0.200 atm

 ⇒ with P1 = the initial pressure = 1.00 atm

W = -nR (210*(0.1/0.2) - 273*(0.1/1.00))

W = -nR*(105 - 27.3)

W= -(0.500)*(8.314)*(77.7)

W = -323 J

b) calculate the internal energy change

E = (3/2)*nRT

ΔE = Ef - Ei

ΔE =(3/2)*nR(T2-T1)

⇒ with n= number of moles = 0.500 moles

⇒ with T2 =the final temperature = 210 K

⇒ with T1 = the initial temperature = 273 K

ΔE = (3/2)*(0.5)*(8.314)(210-273)

ΔE = -392.84 J

c) Calculate the heat absorbed by neon

ΔE = q + W

q = ΔE -W

⇒ with ΔE = -392.84 J

⇒ with W = -323 J

q = -392.84 J -( -323 J)

q =-392.84 J + 323 J

q = -69.84 J

4 0
3 years ago
Other questions:
  • What substance is acting as the Brønsted-Lowry base in the forward reaction below? H2O + HCl yields H3O+ + Cl-
    14·1 answer
  • How many electrons does the isotope oxygen-18 have?<br> 6<br> 8<br> 10<br> 18
    13·1 answer
  • Give the oxidation number of the element indicated for each compound.
    15·1 answer
  • A rock has a mass of 15 grams and a volume of 5 cm3 what is the density of the object
    8·1 answer
  • Ice must absorb heat to melt into water. What must water do to evaporate?
    9·2 answers
  • Determine the ground-state electron configuration and bond order for each of the Period 2 diatomic molecules. Specify which MO i
    8·1 answer
  • QUESTION 7
    9·1 answer
  • How many molecules are there in 5H20?
    13·2 answers
  • Many plants obtain glucose through the process of ___
    15·2 answers
  • Why is it necessary to standardize a secondary standard before use?<br>​
    13·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!