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
Softa [21]
3 years ago
6

Which energy changes in the enthalpy of solution are endothermic, and which are exothermic?

Chemistry
1 answer:
snow_tiger [21]3 years ago
8 0
When energy is needed in order for the reaction to happen, then that reaction is known as endotermic. When the reaction has as a result energy then it is exotermic. An example of an endotermic reaction would be photosynthesis, for an exotermic: combustion.
You might be interested in
The proposed mechanism for a reaction is: Step 1: A + B X (fast) Step 2: X + C Y (slow) Step 3: Y D (fast) What is the overall r
PolarNik [594]

Answer:

(slow)xy2+z→xy2z (fast) c step1:step2:xy2+z2→xy2z2

Explanation:

Step1: xy2+z2→xy2z2 (slow)

Step2: xy2z2→xy2z+z (fast)

2XY 2 + Z 2 → 2XY 2 Z

Rate= k[xy2][z2]

 

When the two elementary steps are summed up, the result is equivalent to the stoichiometric equation. Hence, this mechanism is acceptable. The order of both elementary steps is 2, which is ‘≤3’; this also makes this mechanism acceptable. Furthermore, the rate equation aligns with the experimentally determined rate equation, and this also makes this mechanism acceptable. Therefore, since all the three rules have been observed, this mechanism is possible.

5 0
3 years ago
A radioactive material, with half-life of six months, has 100 thousand unstable nuclei.
goldfiish [28.3K]

Answer:

See Explanation

Explanation:

Given that;

N/No = (1/2)^t/t1/2

Where;

No = amount of radioactive isotope originally present

N = A mount of radioactive isotope present at time t

t = time taken

t1/2 = half life

N/1000=(1/2)^3/6

N/1000=(1/2)^0.5

N = (1/2)^0.5 * 1000

N= 707 unstable nuclei

Since the value of the initial activity of the radioactive material was not given, the activity of the radioactive material after three months is given by;

Decay constant = 0.693/t1/2 = 0.693/6 months = 0.1155 month^-1

Hence;

A=Aoe^-kt

Where;

A = Activity after a time t

Ao = initial activity

k = decay constant

t = time taken

A = Aoe^-3 *0.1155

A=Aoe^-0.3465

3 0
3 years ago
NH3 is a weak alkali that does not dissociate fully into its solution. Which of the following is true about NH3?
ad-work [718]
<h2>NH3 is a weak alkali that does not dissociate fully into its solution. Which of the following is true about NH3? </h2><h2> </h2><h2>A. It has a very low pH. </h2><h2>B. It's dissociation is a reversible reaction. </h2><h2>C. It has a high H+ concentration. </h2><h2>D. It will release all of its OH- ions.</h2>

Explanation:

<h3>NH3 is a weak alkali that does not dissociate fully into its solution: It's dissociation is a reversible reaction. </h3><h3></h3>

Reactions are also :

  • Reversible
  • Irreversible

Reversible reaction

A reaction in which products can combine back to give reactants under same given condition .

Example : N₂+H₂-------NH₃

Irreversible reaction

A reaction in which the products cant combine back to give reactants under same set of conditions .

Example : Burning of paper

3 0
3 years ago
Read 2 more answers
Color, hardness, solubility, mass, density, volume, and melting point are all examples of what type of property?
katovenus [111]

Physical properties.

7 0
3 years ago
Which of the following atoms would be expected to be diamagnetic in the ground state?
Rufina [12.5K]

The atoms that would be expected to be diamagnetic in the ground state is  magnesium

The magnetism of an atom refers to its electronic configuration. A diamagnetic atom is an atom whose electrons are all paired.

A paired electron is an electron that occurs in pairs in its orbital shell.

At their respective ground state, the electronic configuration of the given elements are as follows:

The electronic configuration of magnesium is 1s²2s²2p⁶3s².  As such its a diamagnetic atom.

The electronic configuration of Potassium is 1s²2s²2p⁶3s²3p⁶4s¹. Hence, Potassium has one unpaired electron in its outermost shell.

The electronic configuration of Chlorine is 1s²2s²2p⁶3s²3p⁵. Hence, Chlorine has one unpaired electron in its outermost shell.

The electronic configuration of Cobalt is 1s²2s²2p⁶3s²3p⁶3d⁷4s². Hence, the unpaired electrons of Cobalt in its outermost shell are three.

Therefore, the atoms that are diamagnetic in the ground state is magnesium.

Learn more about diamagnetic atoms here:

brainly.com/question/18865305?referrer=searchResults

8 0
3 years ago
Other questions:
  • The question is what does it regulate. PLEASE HELP. 1 sentence for each will help
    9·2 answers
  • How has the scientific community addressed the safety of chemicals?
    14·1 answer
  • What food group deficiency causes kwashiorkor?? I’ll give 15points
    6·2 answers
  • 24 POINTS!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
    12·2 answers
  • In cats, the allele B is for black fur and allele b is for brown fur. Identify the phenotypes of the following individuals who h
    10·1 answer
  • 3.50 liters of a gas at 727.0 K will occupy how many liters at 153.0 K?
    6·1 answer
  • All formulas of mole concept​
    8·1 answer
  • BRAINLIEST FOR THE FIRST CORRECT ANSWER!! im revising for a test and my teacher gave me some questions to do but i dont understa
    5·1 answer
  • An ideal gas occupies 400ml at 270 mm Hg and 65°C. If the pressure is changed to 1.4 atm and the
    7·1 answer
  • Substance Density (grams/cm3)Chloroform - 1.5Ebony wood - 1.2Mahogany wood - 0.85Oil - 0.9Water - 1.024.A block of ebony wood is
    13·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!