CHEMISTRY HIGH SCHOOL

Which of the following is an exothermic reaction?A.) dissolving sugar in water

B.) melting ice

C.) condensing steam

D.) dissolving ammonium nitrate in water

Answers

Answer 1
Answer:

Answer:

C.) condensing steam

Explanation:

Exothermic reactions are chemical reaction which energy is released to the environment in the form of heat . The overall energy of the reactant is greater than the energy of the product. The higher in energy of the reactant causes a release of heat to the environment. In exothermic reactions, enthalpy change is  usually negative and is accompanied by the loss of energy in the form of heat or light.

Condensation is the change of water vapor to liquid . The conversion is an exothermic reaction as energy is release to the environment in the form of heat.  The water vapor molecules has higher energy than liquid. The changes of water vapor to liquid causes a loss in energy of the water vapor. As the water vapor loss more energy, heat is been release to the surrounding.

All other reaction are endothermic in which heat is absorb from the environment except for condensation of steam.

Answer 2
Answer:

The event that is an example of an exothermic reaction is condensing steam. The answer is letter C. An exothermic reaction is one in which there is a release of heat during the reaction. Dissolving sugar in water, melting ice and dissolving ammonium nitrate in water are all examples of an endothermic reaction.

Related Questions

The standard enthalpy of ________ is the enthalpy change of reaction to form one mole of a substance from its elements under standard conditions of temperature and pressure.
5. Which quantities must be conserved in all chemical reactions?
An atom has an atomic number of 12 and a mass number of 25. How many neutrons does the atom have?12 13 25 37
A 115.0-g sample of oxygen was produced by heating 400.0 g of potassium chlorate.What is the percent yield of oxygen in this chemical reaction?
Carbon-13 is an isotope of carbon. The atomic number of carbon is 6. How many neutrons does carbon-13 have?

tert-Butyl alcohol is a solvent with a Kf of 9.10 ∘C/m and a freezing point of 25.5 ∘C. When 0.807 g of an unknown colorless liquid was dissolved in 11.6 g of tert-butyl alcohol, the solution froze at 15.3 ∘C.Which of the following is most likely the identity of this unknown liquid?tert-Butyl alcohol is a solvent with a of 9.10 and a freezing point of 25.5 . When 0.807 of an unknown colorless liquid was dissolved in 11.6 of tert-butyl alcohol, the solution froze at 15.3 .Which of the following is most likely the identity of this unknown liquid?ethylene glycol (molar mass = 62.07 g/mol)1-octanol (molar mass = 130.22 g/mol)glycerol (molar mass = 92.09 g/mol)2-pentanone (molar mass = 86.13 g/mol)1-butanol (molar mass = 74.12 g/mol)

Answers

Answer: ethylene glycol (molar mass = 62.07 g/mol)

Explanation:

Depression in freezing point :

Formula used for lowering in freezing point is,

\Delta T_f=k_f* m

or,

\Delta T_f=k_f* \frac{\text{mass of solute}}{\text{molar mass of solute}* \text{weight of solvent in kg}}

where,

T_f = change in freezing point

k_f = freezing point constant= 9.10^0C/m

m = molality

Given mass of solute = 0.807 g

Molar mass of solute=? g/mol

weight of solvent in kg= 11.6 g=0.0116 kg

\Delta T_f=T^(o)_f-T_f=25.5^0C-15.3^0C)=10.2^0C

10.2=9.10* \frac{0.807}{\text{molar mass of solute}* 0.0116kg}

{\text{molar mass of solute}}=62.07 g/mol

Thus the solute is ethylene glycol which has same molecular mass as calculated, i.e 62.07 g/mol.

Boyle’s law states that the volume of a gas is inversely proportional to its pressure if theA. temperature and number of particles are constant.
B. temperature reaches absolute zero.
C. number of particles decreases.
D. temperature and number of particles are doubled

Answers

Boyle's law states that the volume of a fixed mass of a gas is inversely proportional to its temperature if the temperature and the number of particles are constant.

Further Explanation

Boyles’s law  

  • This gas law states that the volume of a fixed mass of a gas is inversely proportional to its pressure at constant absolute temperature.
  • Therefore, when the volume of an ideal gas is increased at constant temperature then the pressure of the gas will also increase.
  • Mathematically;  Volume α 1/Pressure

                               Vα1/P

  • Therefore, constant k, is = PV

Other gas Laws

Gay-Lussac’s law  

  • It states that at constant volume, the pressure of an ideal gas I directly proportional to its absolute temperature.
  • Thus, an increase in pressure of an ideal gas at constant volume will result to an increase in the absolute temperature.

Charles’s law

  • It states that the volume of a fixed mass of a gas is directly proportional to absolute temperature at constant pressure.
  • Therefore, an increase in volume of an ideal gas causes a corresponding increase in its absolute temperature and vice versa while the pressure is held constant.

Dalton’s law  

  • It is also known as the Dalton’s law of partial pressure. It states that the total pressure of a mixture of gases is always equivalent to the total sum of the partial pressures of individual component gases.
  • Partial pressure refers to the pressure of an individual gas if it occupies the same volume as the mixture of gases.

Keywords: Gas law, Boyles's law, pressure, volume, absolute temperature, ideal gas

Learn more about:

Level: High school

Subject: Chemistry

Topic: Gas laws

Sub-topic: Boyle's Law  

Final answer:

Boyle's law states the volume of a gas and its pressure are inversely related, given that temperature and number of particles are constant. Increased pressure leads to decreased volume and vice versa, providing temperature and the amount of gas remains the same.

Explanation:

Boyle's law, part of the field of Physics, specifically the subsection dealing with gas laws in Chemistry, states that the volume of gas is inversely proportionate to its pressure, under the condition that the temperature and number of particles of gas are constant. This means if the pressure of a gas increases, its volume decreases and vice versa. To clarify, let's consider an example. If you have a balloon filled with air (the gas), when you squeeze it (increasing pressure), the balloon gets smaller (volume decreases). However, this law only holds when the temperature and the number of gas particles are constant; no additional gas is added, nor heat.

Learn more about Boyle's Law here:

brainly.com/question/2862004

#SPJ6

What determines the strength of a dipole-dipole force?A. The more symmetrical the molecule, the stronger the force.
B. The more hydrogen in the molecule, the stronger the force.
C. The more polar the molecules, the stronger the force.
D. The larger the atomic radius, the stronger the force.

Answers

The more polar the molecules, the stronger the force. Hence, option C is correct.

What is dipole-dipole force?

Dipole-Dipole forces are the interaction between molecules of the permanent dipole. It occurs between the partially charged positive molecules and partially charged negative molecules.

Polar molecules align themselves so that the δ– end of one molecule is near the δ+ ends of other molecules.

The molecules are thus attracted to each other. Dipole-dipole forces exist between polar molecules.

The greater the polarity, the stronger the dipole-dipole forces.

Hence, option C is correct.

Learn more about dipole-dipole force here:

brainly.com/question/14195217

#SPJ5
The answer is C: the more polar the molecules, the stronger the force. Hope this helps!

in a school’s laboratory, students require 50.0 mL of 2.50 M H2SO4 for an experiment, but the only available stock solution of the acid has a concentration of 18.0 M. What volume of the stock solution would they use to make the required solution? Use mc018-1.jpg.

Answers

Ans: Volume of stock H2SO4 required = 6.94 ml

Given:

Concentration of stock H2SO4 solution M1 = 18.0 M

Concentration of the final H2SO4 solution needed M2 = 2.50 M

Final volume of H2SO4 needed, V2 = 50.0 ml

To determine:

Volume of stock needed, V1

Explanation:

Use the dilution relation:

M1V1 = M2V2\n\nV1 = (M2V2)/(M1) \n\nV1  = (2.50 M * 50.0 ml)/(18.0 M) = 6.94 ml

Hello!

In a school’s laboratory, students require 50.0 mL of 2.50 M H2SO4 for an experiment, but the only available stock solution of the acid has a concentration of 18.0 M. What volume of the stock solution would they use to make the required solution?  

We have the following data:

M1 (initial molarity) = 2.50 M (or mol/L)

V1 (initial volume) = 50.0 mL → 0.05 L

M2 (final molarity) = 18.0 M (or mol/L)

V2 (final volume) = ? (in mL)

Let's use the formula of dilution and molarity, so we have:

M_(1) * V_(1) = M_(2) * V_(2)

2.50 * 0.05 = 18.0 * V_(2)

0.125 = 18.0\:V_2

18.0\:V_2 = 0.125

V_2 = (0.125)/(18.0)

V_2 \approx 0.00694\:L \to \boxed{\boxed{V_2 \approx 6.94\:mL}}\:\:\:\:\:\:\bf\green{\checkmark}

Answer:

The volume is approximately 6.94 mL

_______________________________

\bf\green{I\:Hope\:this\:helps,\:greetings ...\:Dexteright02!}\:\:\ddot{\smile}

Calculate the pH of a solution that is 0.111 M HCl. PH=?

Answers

HCl(aq) ------> H⁺(aq)  + Cl(aq)  
     ↓                    ↓            ↓
i :   0.111 M          0               0
v: - 0.111 M     +0.111 M   +0.111 M
_______________________________
eq:    0            +0.111 M    +0.111 M 

HCl is a strong acid, so it ionizes 100% in solution :

PH = - log [ H+]

PH = - log [ 0.111]

PH = 0.9546

hope this helps!

When sodium metal is added to water, an orange flame is observed on the metal surface. Based on this observation, what can best be concluded

Answers

Answer:

the answer i belive is c

Explanation:

A chemical reaction occurs because heat and light are given off.

Explanation:

A property which causes change in chemical composition of a substance is known as a chemical property. For example, reactivity, toxicity, combustion etc.

Whereas a property which causes no change in chemical composition of a substance is known as a physical property. For example, mass, volume, density etc.

Sodium is a very reactive metal and it reacts readily with oxygen, water etc. So, when sodium is added to water then occurrence of an orange flame represents its reactivity.

Thus, based on given observation it can be concluded that chemical reaction takes place when sodium is added to water.
Other Questions
OSHA standards appear in the ___________ and are then broken down into ____________.
The gravitational force acting on an object is also called the object's _____. A) mass B) weight C) density D) volume​
The state of matter that is able to be compressed is gas liquid solid
Thermal expansion or thermal contraction would be most noticeable in which of the following?A. Hot car seat B. Concrete in a sidewalk C. Air inside a balloon D. Liquid in a drink