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
pashok25 [27]
2 years ago
6

The atomic number of an element:

Chemistry
1 answer:
Aleonysh [2.5K]2 years ago
6 0

Answer:

I think #3 might be the answer .

Because in #1 atomic mass tells mass .

#4 Atomic number doesnot only tell about the electrons atom has

You might be interested in
What is the significance of "Er" in the diagram?
Drupady [299]

Answer:

The significance of "Er" in the diagram is :

B.) Threshold energy for reaction

Explanation:

Threshold energy : It is total amount of energy required by the reactant molecule to reach the transition state .

Activation energy : It is the excess energy absorbed by the molecules to reach the transition state.

<u>Activation Energy = Threshold Energy - Average Kinetic Energy</u>

<u>This means Activation energy decreases on increasing kinetic energy</u>

On increasing Temperature average kinetic energy of the molecule increases which reduces the activation energy and the reaction occur faster in that case.

Catalyst also reduces the Activation energy.

<u>Er = Threshshold energy for reaction at 30 degree</u>

<u>Ea = Activation Energy</u>

<u>The given figure shows that the threshold energy decreases on increasing the temperature</u>

<u>Only the molecule having energy greater than Er can react to form product</u>

3 0
3 years ago
Read 2 more answers
What protects living things from too much ultraviolets radiation?
mixas84 [53]
The ozone layer of the Earth's atmosphere is what protects living things from too much ultraviolet radiation, if that's what you're asking about. 
8 0
3 years ago
NItrogen in air reacts at high temperature to form NO2 according to the reaction:
Rina8888 [55]

Answer:

The correct answer is option E.

Explanation:

Structures for the reactants and products are given in an aimage ;

Number of double bonds in oxygen gas molecule = 1

Number of double bonds in nitro dioxide gas molecule = 1

Number of single bond in in nitro dioxide gas molecule = 1

Number of triple bonds in nitrogen gas molecule = 1

N_2+2O_2\rightarrow 2NO_2,\Delta H=?

\Delta H=[2 mol\times \Delta H_{f,NO_2}]-[1 mol\times \Delta H_{f,N_2}-2 mol\times \Delta H_{f,O_2}]

\Delta H_{f,NO_2}=33.18 kJ/mol

\Delta H_{f,N_2}=0 (pure element)

\Delta H_{f,O_2}=0 (pure element )

\Delta H=2 mol\times 33.18 kJ/mol=66.36kJ=15.86 kcal

The enthalpy of the given reaction is 15.86 kcal.

6 0
3 years ago
Calculate the concentration of an aqueous solution of naoh that has a ph of 11.50
Reika [66]
NaOH is a strong base and complete dissociation into Na⁺ and OH⁻ ions. 
Therefore [NaOH] = [OH⁻]
To calculate the [OH⁻], we can first find the pOH as NaOH is a basic solution.
pH + pOH = 14
Since pH = 11.50
pOH = 14 - 11.50
pOH = 2.50
We can calculate [OH⁻] by knowing pOH 
pOH = -log[OH⁻]
[OH⁻] = antilog(-pOH)
[OH⁻] = 3.2 x 10⁻³ M
therefore [NaOH] = 3.2 x 10⁻³ M
7 0
3 years ago
Read 2 more answers
Which property describes a mixture? It cannot be separated by physical methods. It has a single chemical composition. It cannot
natima [27]

Answer:

it cannot be separated by physical methods

Explanation:

7 0
3 years ago
Read 2 more answers
Other questions:
  • List three methods of radiometric dating, and
    11·1 answer
  • Copper and silver are examples that will form what bond
    7·1 answer
  • How many moles of HCL are in 20 ml sample of .10 M HCL
    8·1 answer
  • What is the Moleular geometry of Xe0F4
    6·1 answer
  • An animal skeleton has a carbon-14 decay rate of 13.1 disintegrations per minute per gram of carbon. When did the animal die? (A
    13·1 answer
  • I need help with this science question ​
    6·1 answer
  • Which organelle acts as a temporary storage center, containing water,
    6·2 answers
  • I need help please on chemistry
    11·1 answer
  • Determine la temperatura Kelvin de 2.49 moles de gas contenido en un
    6·1 answer
  • How many moles of xenon trioxide are present in 1. 69 grams of this compound.
    10·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!