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
professor190 [17]
3 years ago
7

Help me please !! is it A,B,C, or D ???

Chemistry
1 answer:
Nata [24]3 years ago
5 0
Ok, after doing an immense amount of research I came up with the most logical answer.

A. Is indicated by a negative enthrall sign.

Reasoning: an endothermic reaction is ice melting and the energy being more than its surroundings. Not specified to ice but as an example, ice is endothermic. That puts d and b out of the running leaving you left with a and c.

When I searched up enthalpy, it said “When a substance changes at constant pressure, enthalpy tells how much heat and work was added or removed from the substance.” Which is similar to c, right? Yeah, meaning both a and c are similar in that aspect.

The reason I decided to go with a is because heat is NOT released into the surrounding, exothermic reactions release energy and heat into the surrounding.
You might be interested in
How much silver is produced is 15.00 grams of cu is added to the solution of excess silver nitrate?
il63 [147K]
First write out the balanced equation. 3Cu+2Ag(NO3)3=2Ag+3Cu(NO3)2
Then convert copper from grams to moles
15 g*1 mol cu/63.54 g= 15/63.54 mol cu
Then use the mole ratio to convert Moles Cu to Moles Ag
15/63.54 moles Cu* 2 moles Ag/3 moles Cu
The final awnser is (15*2)/(63.54*3) moles Ag =0.157 moles Ag. If the question wants the answer in grams, convert from moles Ag to grams Ag.
0.157 moles Ag*107.87 g Ag/ mol Ag=16.98 g Ag
6 0
3 years ago
What are small round structures in the cell that breaks down large food particles into smaller ones
Oxana [17]
The small particles are known as protiens
4 0
3 years ago
Read 2 more answers
Given that w for water is 2. 4×10−14 m^2 at 37 °C. Calculate the ph of a neutral aqueous solution at 37 °c, which is the normal
alexgriva [62]

The pH of a neutral aqueous solution at 37°C is 6.8.

<h3>What is Kw? </h3>

Kw is defined as the dissociation, which is also known as self-ionization, constant of water. this is an equilibrium constant, and its expression is:

Kw = [OH⁻] . [H₃O⁺]

Neutral pH determines that the concentrations of OH⁻ and H₃O⁺ are equal.

<h3>Calculation</h3>

Let us suppose concentration of OH and H₃O⁺ is x, to calculate it:

Kw =[OH⁻] . [H₃O⁺] = x²

x² = 2.4 × 10⁻¹⁴ M²

x = 1.5919 × 10⁻⁷ M

Hence, the concentration of OH and H₃O⁺ (x) = [H₃O⁺] = [OH⁻] = 1.5919×10⁻⁷ M

pH = -log[H₃O⁺] = -log( 1.5919×10⁻⁷ M)

pH = 6.8

Thus, we find that the pH of a neutral aqueous solution at 37 °c (which is the normal human body temperature) is 6.8.

learn more about pH:

brainly.com/question/9529394

#SPJ4

3 0
1 year ago
3. Burns from boiling water can be severe, caused by the transfer of energy from the boiling water to the
Free_Kalibri [48]

Answer:

Q = 3937.56  J

Explanation:

Heat transferred due to change in temperature is given by :

Q=mc\Delta T

c is the specific heat of water, c=4.18 J/g-°C

We have, m = 15 g, T_i=100^{\circ} C\ \text{and}\ T_f=37.2^{\circ} C

So,

Q=15\times 4.18\times (37.2-100)\\Q=-3937.56\ J

Hence, 3937.56  J of heat is transferred.

8 0
3 years ago
What do astronomers use to calculate the age of the universe? Select three options.
sasho [114]

The answers are

The age of the oldest stars

How fast distant galaxies are moving away from us

Patterns of background radiation.

Explanation:

The Astronomers calculate the age of the universe by looking for oldest stars, and by measuring the rate of expansion of the universe and back to big bang.

The Astronomers used the techniques like the age of oldest stars, how fast the distant galaxies are moving away from us, patterns of background radiation and along with the Big Bang as reference point, they estimate that the universe may be approximately 12 billion years old.

7 0
3 years ago
Other questions:
  • How many liters of a 0.50 solution are needed to give 3.5 moles of solute
    12·2 answers
  • Draw Au3N as a picture of atoms
    6·1 answer
  • Dry ice sublimes into carbon dioxide gas. If the proper conditions are maintained and the system is closed, the dry ice and the
    12·1 answer
  • 5. How many significant figures are in the measurement +0.500 mg?
    7·1 answer
  • Snape has 2000 mL of a magic potion solution that is $30\%$ DeMuggle Juice. He also has hundreds of 25 mL bottles that are full
    9·1 answer
  • What family is the mineral lead in?
    11·1 answer
  • What is carbon -12 scale<br>​
    8·1 answer
  • MY ELEMENT IS SODIUM
    7·1 answer
  • The genome map with details for gene 4 on chromosome 6 _____.
    7·1 answer
  • (HELP) Vanessa is conducting an experiment to see how exposure to different types and amounts of light affects the growth of pea
    6·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!