All categories

3 years ago

29. What is E for a system which has the following two steps:

Chemistry

1 answer:

jasenka [17]3 years ago

4 0

Answer:

Zero

Explanation:

Recall that;

E = q + w

Where;

q = heat, w = work done

When heat is absorbed by the system q is positive

When heat is evolved by the system q is negative

When the system does work, w is negative

When work is done on the system w is positive

Step 1

ΔE1= 60 KJ + 40 KJ = 100KJ

Step 2

ΔE2= (-30 KJ) + (-70 KJ) = (-100) KJ

ΔE1 + ΔE2= 100KJ + (-100) KJ = 0KJ

You might be interested in

Complete and balance the precipitation reactions. Include physical states. Refer to the solubility rules as necessary. precipita

Tcecarenko [31]

The balanced chemical reactions are:

$AgNO{_3}(aq) \ + \ NaCl(aq) \rightarrow \ AgCl(s) \ + NaNO_{3}(aq)\\2K_{3}PO_{4}(aq) \ + 3MgCl_{2}(aq) \rightarrow \ 6KCl(aq) \ + Mg_{3}(PO_{4})_{2}(s)$

Further Explanation:

The following reactions will undergo double displacement where the metal cations in each compound are exchanged and form new products.

For reaction 1, the compounds involved are nitrates and chlorides. To determine the states of the products, the solubility rules for nitrates and chlorides must be followed:

All nitrates are generally soluble.
Chlorides are generally soluble except AgCl, PbCl2, and Hg2Cl2.

Therefore, the products will have the following characteristics:

silver chloride (AgCl) is insoluble
sodium nitrate (NaNO3) is soluble

For reaction 2, the compounds involved are phosphates and chlorides. The solubility rules for phosphates and chlorides are as follows:

Phosphates are generally insoluble except for Group 1 phosphates.
Chlorides are generally soluble except for AgCl, PbCl2, and Hg2Cl2.

Hence, the products of the second reaction will have the following characteristics:

potassium chloride (KCl) is soluble
magnesium phosphate is insoluble

Insoluble substances are denoted by the symbols (s) in a chemical equation. The soluble substances are denoted as <em>(aq).</em>

Learn More

Learn more about solubility brainly.com/question/1163248
Learn more about solubility rules brainly.com/question/1447161
Learn more about net ionic equations brainly.com/question/12980075

Keywords: solubility rules, precipitation reaction

3 0

3 years ago

If you feel warm after exercising, have you increased the internal energy of your body? Explain.

elena-s [515]

If we feel warm after exercising, it means that the temperature of the surroundings has increased. Therefore, heat is released from our body (energy transferred from the system to the surroundings) which means the internal energy of our body is decreased after exercising.

internal energy U is the sum of the kinetic energy brought about by the motion of molecules and the potential energy brought about by the vibrational motion and electric energy of atoms inside molecules in a system or a body with clearly defined limits. The energy contained in every chemical link is often referred to as internal energy. From a microscopic perspective, the internal energy can take on a variety of shapes. For any substance or chemical attraction between molecules.

Internal energy is a significant amount and a state function of a system. Specific internal energy, which is internal energy per mass of the substance in question, is a very intense thermodynamic characteristic that is often represented by the lowercase letter U. As a result, the J/g would be the SI unit for internal specific energy. The term "molar internal energy" and the unit "J/mol" might be used to describe internal energy that is expressed as a function of the quantity of a substance.

Learn more about internal energy brainly.com/question/11278589

#SPJ4

6 0

1 year ago

Explain what temperature is a measurement of.

skad [1K]

Inches because that is a trait of measurement

5 0

3 years ago

A volatile liquid is one that ______?

nasty-shy [4]

readily evaparates.

hope it helped :D

7 0

3 years ago

The empirical formula for carbohydrates is CH2O. The molecular weight for a particular carbohydrate is 90.09 grams. What is the

baherus [9]

We find the weight of the empirical formula:
12.0107 + 2 x 1.00794 + 15.9994
= 30.03

Now, we divide the molecular weight by the weight of the empirical formula to find the number of times the empirical formula repeats:
90.09 / 30.03
= 3

The formula is 3(CH₂O)
C₃H₆O₃

6 0

3 years ago