Use the heat equation to find out how many joules of energy are needed
to raise the temperature of 67 grams of water form 20°C - 45°C. What is the
answer in kilojoules?
(specific heat of water is 4.2 J/gºC.)

Answers

Answer 1

Answer:

About 7.0 × 10³ J or 7.0 kJ

Explanation:

We want to determine the amount of energy needed to raise the temperature of 67 grams of water from 20°C to 45°C.

We can use the heat equation:

[tex]\displaystyle q = mC\Delta T[/tex]

Where C is the specific heat of water.

Substitute and evaluate:

[tex]\displaystyle \begin{aligned} q & = (67\text{ g})\left(\frac{4.2\text{ J}}{\text{g-$^\circ$C}}\right)\left(45^\circ \text{ C}- 20.^\circ\text{ C}\right) \\ \\ & = (67\text{ g})\left(\frac{4.2\text{ J}}{\text{g-$^\circ$C}}\right)(25^\circ \text{ C}) \\ \\ & = 7.0\times 10^3 \text{ J}\end{aligned}[/tex]

Recall that there are 1000 J in a kJ. Hence:

[tex]\displaystyle \begin{aligned} q & = 7.0\times 10^3 \text{ J} \cdot \frac{1\text{ kJ}}{1000\text{ J}} \\ \\ & = 7.0 \text{ kJ}\end{aligned}[/tex]

In conclusion, it will take about 7.0 × 10³ J or 7.0 kJ of energy to raise the temperature of 67 grams of water from 20 °C to 45 °C.


Related Questions

Check all of the following below which describe experimental errors that would affect the percent chloride you report in your experimental results: ____________
a) The solid product was wet when you weighed the final mass
b) You added excess silver nitrate into the reaction mixture
c) The liquid collected from the filtration was cloudy
d) The transfer from the reaction beaker to the filter funnel was imperfect (you lost some of the reaction solution or some was left in the beaker)
e) Extra water was used to dissolve the original unknown solid

Answers

The options that describe the experimental errors that would affect the percent of chloride reported are:

B (You added excess silver nitrate into the reaction mixture) and D (The transfer from the reaction beaker to the filter funnel was imperfect).

While performing experiments, there are some errors that occur which are generally known as experimental errors.

These experimental errors are the difference between the true measurement and what we measured.

There are three types of experimental errors they include:

systematic,

random, and

human error.

Human errors occur due to carelessness of the observer.

Examples are:

when you added excess silver nitrate into the reaction mixture

when the transfer from the reaction beaker to the filter funnel was imperfect due to lost of some of the reaction solution.

Therefore, the options describe the experimental errors that would affect the percent of chloride reported are B and D.

Learn more about experimental errors here:

https://brainly.com/question/2764830

WILL GIVE BRAINLIEST (also pls don't copy answers from other ppl :D) Question: Choose two spheres of Earth which interact when hot springs are formed. Use complete sentences to explain how they interact during this process.

Answers

Answer:

Geosphere and Hydrosphere.

Explanation:

Hot springs are heated by geothermal heat—heat from the Earth's interior. In volcanic areas, water may come into contact with very hot rock heated by magma. The geosphere and hydrosphere interact when hot springs form. The geosphere gets a little melted by the hot hydrosphere and then when the springs shoot up in the air they break some rocks.

A 4.190 g sample of an oxide of chromium contains 2.179g of chromium, what is its empirical formula?

a. CrO2
b. Cr2O
c. CrO3
d. Cr2O3

Answers

I'm not sure but I think it is C. CrO3

need little help pls

Answers

Answer:

0.354 molal

Explanation:

The molarity (M) or the concentration of a solution is defined as the number of moles of a compound in the solution per liter of solution (mol/L), whereas molality, is defined as the number of moles of a compound in the solution per kg of the compound (mol/kg).

Given that the density of the solution is 1.202 g/mL, which is equivalent to 1.202 kg/L. Since the prefix mili- denotes a factor of one thousandth ( [tex]10^{-3}[/tex] ) and kilo- denotes a factor of one thousand ( [tex]{10}^3[/tex] ),

[tex]1.202 \ \frac{g}{mL} \ = \ 1.202 \ \frac{g}{(10^{-3}) L} \ = \ 1.202 \ \frac{{10}^3g}{L} \ = \ 1.202 \ \frac{kg}{L}[/tex].

To calculate the corresponding molality of the solution, the formula

[tex]Molality \ (mol/kg) \ = \ \frac{Molarity \ (mol/L)}{Density \ (kg/L)}[/tex] is used.

Therefore,

[tex]Molality \ = \ \frac{0.426 \ mol/L}{1.202 \ kg/L} \ = \ 0.354 \ mol/kg \ \ (3 \ s.f.)[/tex]

Which statement describes a homogeneous catalyst?
It is in a gaseous phase only.
It is in the same phase as the reactants.
It is completely consumed by reactants.
It forms different products than the uncatalyzed reaction forms.

Answers

Answer:

it is in the same phase as the reactants

The  statement describes a homogeneous catalyst is,

It is in the same as the reactants.

So, option B is correct one.

What is  homogeneous catalyst?The  homogeneous catalyst is refer to catalytic system.In this, the phase of substrates for a reaction and catalytic components are same.Mainly it is in liquid phase.Example: Production of acetic acid

What is catalyst?

The substance which increases the rate of the reaction without being itself change at the end of the reaction is called catalyst.

learn about homogeneous catalyst,

https://brainly.com/question/4249142

#SPJ2

1. Which of the following shows the process of freezing?'
A.candle wax cooling on the table
B.pouring cola over ice
C. heating a cup of water
D. particles are speeding-up and colliding more

Answers

A. because the wax was hot meaning it’s molecules are moving fast and then cooling down which slows down the molecules. this is the same thing that happens when water changes it’s state to ice

Answer:

A. candle wax cooling on the table

Explanation:

Candle wax cooling on a table is an example of freezing because the atoms in the candle wax start to slow down as the wax cools. This is considered "freezing" because the slower an atom is vibrating then the colder it is and of course the faster an atom is vibrating then the hotter it is! :)

Mole problems. See the image for reference. Please show your work.

Answers

Sorry you’ll need to attach an image

How do plants use the energy from the sunlight?

Answers

Answer:

Hey mate....

Explanation:

This is ur answer....

Plants use a process called photosynthesis to make food. During photosynthesis, plants trap light energy with their leaves. Plants use the energy of the sun to change water and carbon dioxide into a sugar called glucose. Starch is stored in seeds and other plant parts as a food source.

Hope it helps!

Brainliest pls!

Follow me! :)

Answer:

Plants use photosynthesis to convert sun light into their own food to consume. Green plants use this light energy to change water and carbon dioxide into oxygen and nutrients called sugars. The plants use some of the sugars and store the rest. The oxygen is released into the air.

A student wants to determine the melting point of water as part of an investigation into the strength of electrostatic forces. The student considers determining the freezing point of water instead. Is this a valid option?

Answers

According to the forces of attraction freezing point and boiling point of water are different and are not related to  strength of electrostatic forces.

What are forces of attraction?

Forces of attraction is a force by which atoms in a molecule  combine. it is basically an attractive force in nature.  It can act between an ion  and an atom as well.It varies for different  states  of matter that is solids, liquids and gases.

The forces of attraction are maximum in solids as  the molecules present in solid are tightly held while it is minimum in gases  as the molecules are far apart . The forces of attraction in liquids is intermediate of solids and gases.

The physical properties such as melting point, boiling point, density  are all dependent on forces of attraction which exists in the substances.

Learn more about forces of attraction,here:

https://brainly.com/question/23841038

#SPJ2

USCTIR ENFIK meaning?

Answers

Answer:

la branche de la mécanique concernée par le mouvement des objets sans référence aux forces qui provoquent le mouvement

Answer:

the features or properties of motion in an object.

What is the correct form of the equilibrium constant for the reaction of hydrogen and oxygen to form water? The equation is:

2H 2( g) + O 2( g) ⇌ H 2O( g)

Kc = ([H2O]/[O2] [H2])

Kc = ([H2O]/[O2] [H2]2)

Kc = ([H2O]/[O2] [H22])

Kc = ([H2O]2/[O2] [H22])

Kc = ([H2O]/[O2] [2H2])

Answers

answer :

the second one.




Draw the Lewis structures for

Calcium bromide, CaBr2

Answers

Since Calcium contains TWO valence electrons, it can donate each electron to each Br atom. Hence, Ca gains a charge of 2+ whereas each Br gains a 1-

The Lewis structure is the way of expressing the covalent bonding in molecules. The covalent bond formation takes place by the sharing of electrons in a molecule.

What is Lewis structure?

In Lewis dot structures or simply the Lewis structures, the dots are used to represent the electrons. They provide a picture of bonding in molecules in terms of the shared pair of electrons and the octet rule.

The concept of covalent bond is introduced by the scientist G.N Lewis. According to him, the atoms achieve stable octet when they are linked with each other by sharing of one more pairs of electrons. The covalent bonding occurs between the atoms which do not differ much in their electronegativity.

The Lewis structure of CaBr₂ is denoted below. Here two bromine atoms acquires a stable electronic configuration by sharing electrons. There are two single bonds between them.

To know more about Lewis structure, visit;

https://brainly.com/question/20300458

#SPJ5

( picture ) identify each type of reaction shown below

Answers

it wouldnt let me type it because it said it was too inappropriate

Explanation:

I’m not sure if it’s the square on the right or left. Please help

Answers

Answer:OK im not 100% sure but it should be the right one

Explanation:

It should DEFINITELY be the square on the right.

Which property is the same for a 50 mL sample of liquid water and a 100 mL sample of liquid water?

Answers

Answer: The density because it stays the same with any same liquids or solids or gas with whatever amount of it is added. It only changes if the matter of state is different or there is any environmental change.

All of the following compounds are soluble in water EXCEPT

a
MgSO4
b
Ca(NO3)2
с
Agi
d
K2CO3

Answers

Answer:

Anser is C Agl

Explanation:

Agl does not dissolve in water.

All of the following compounds are soluble in water except AgI because of  very high value of lattice energy. Therefore, the correct option is option C.

The capacity of a material, the solute, to combine with a different material, the solvent, is known as solubility in chemistry. Insolubility, or the solute's inability to create such a solution, is the opposite attribute. The concentration for the solute within a saturated solution—a solution where no more of the substance can be dissolved—is typically used to gauge the degree of a substance's solubility in a particular solvent. The two compounds are considered to be at the point of solubility equilibrium at this time. All of the following compounds are soluble in water except AgI because of  very high value of lattice energy.

Therefore, the correct option is option C.

To know more about lattice energy, here:

https://brainly.com/question/29735933

#SPJ6

which is the compound that has the higher boiling point and explain why we see the

differences we do

a. ethane vs. ethene

b. heptyne vs. pentyne

c. octane vs. octanal

thanks!

Answers

Answer:

b I think it is the correct answer

Explain the verse below in your own words in a little summary.




Hebrews 11:7

Answers

God had warned Noah of the flood and directed him to build an ark. Noah had faith in God and began building.

Answer:

God Warned Noah for the Flood comindg to Earth to wash away all the bad people's lives and god also said get couple animals girls and boys then build an ark then bring your family and food there to then noah had a faith in god so he obey and start builind the ark in a top of a mountain

Explanation:

Hebrews 11:7

Fill in the blank for the following statement: ________ is the movement of rocks, sand, or materials from a place?

Answers

Answer:

Erosion.

Explanation:

It can be as small as a grain of sand or as large as a boulder. Sediment moves from one place to another through the process of erosion. Erosion is the removal and transportation of rock or soil. Erosion can move sediment through water, ice, or wind.

The Answer is erosion

What is the lowest frequency photon that can ionize a hydrogen atom with excited state electron configuration 3s^1?

Answers

67 because it’s the lowest frequency photon

why are electric switches and boards are made up of plastic

Answers

Question:-

why are electric switches and boards are made up of plastic

Answer:-

Because plastic is a poor conductor of electricity.

Explanation:-

Plastics do not conduct enough heat and electricity. Therefore, it is used in the manufacture of plug switches, plug boards, etc.

How many moles are in 500 g of P

Answers

Answer:

.....................

30.973761


Help i dont get it

Answers

Answer:

2. Products; FeCl2 and H2S

Reactants; FeS and HCl

3. a) 36g of water

b) 64g of oxygen

Could a single person or animal be a point source pollution

Answers

Yes, mostly humans do things 24/7 that pollutes the air around us

Answer:

the main cause of pollution is mankinds work like gases and extreme heat caused by factories and cars and littering is also caused by people's careless throwing away so In term man kind is responsible for the pollution

Explanation:

what is oxidation number on Ni in the next compound
K2[NiBr6] ???

Answers

Explanation:

The oxidation number of Ni is +4

Calculate the emf of the following concentration cell: Au(s) | Au3+ (0.10 M) || Au3+ (0.50 M) | Au(s)

Answers

The emf of the cell as written is calculated to be  0.014 V.

Using the Nernst equation;

Ecell = E°cell - 0.0592/n log Q

We must note that  E°cell = 0 because the anode and cathode are composed of the same type of metal.

Now;

Substituting values, we have;

Ecell = 0 -  0.0592/3 log (0.50 M)/(0.10 M)

Ecell = 0.014 V

Learn more: https://brainly.com/question/15394851

the normal human eye responds to visible light of wavelength range from about 390 to 710nm. Determine the frequency range of the human eye.​

Answers

Explanation:

=>7.7 x10¹⁴ to 4.2 x10¹⁴Hz

A 33.4−L volume of methane gas is heated from 22°C to 66°C at constant pressure. What is the final volume of the gas?

Answers

Answer:

38.38 L (3 d.p.)

Explanation:

In response to questions addressing the expansion of gas via heating, Charles's Law should be considered. Charles's Law is an experimental gas law explaining the tendency of gases to expand when heated.

The law states that the volume ([tex]V[/tex])  of a gas is directly proportional to its temperature ([tex]T[/tex]) given that the pressure ([tex]P[/tex]) and the amount of gas ([tex]N_{A}[/tex]) are constant.

[tex]\displaystyle\frac{V}{T} \ = \ k \ \ \ \ \ \ \ or \ \ \ \ \ \ \ V \ = \ kT[/tex], where k is a proportionality constant.

*Note that when substituting temperature into the equation, the temperature must be in terms of the Kelvin scale and not in degrees Celsius. The relation between the Kelvin scale and the Celsius scale is  [tex]\mathrm{K} \ = \ ^{\circ}\mathrm{C} \ + \ 273[/tex].

Charles's law can be used to compare changing conditions of a particular gas. Let  [tex]V_{1}[/tex]  and  [tex]T_{1}[/tex]  be the initial volume and temperature for the gas, while  [tex]V_{2}[/tex]  and  [tex]T_{2}[/tex]  be the final volume and temperature. The mathematical relationship of Charles's law becomes:

[tex]\displaystyle\frac{V_{1}}{T_{1}} \ = \ \displaystyle\frac{V_{2}}{T_{2}}[/tex].

In accordance with the question,

[tex]V_{1} \ = \ 33.4 \ \mathrm{L}, \ T_{1} \ = \ (22 \ + \ 273) \ \mathrm{K} \ = \ 295 \mathrm{K}, \ T_{2} \ = \ (66 \ + \ 273) \ \mathrm{K} \ = \ 339 \ \mathrm{K}[/tex]

while  [tex]V_{2}[/tex]  is the final volume of the gas that we would like to find. Therefore,

[tex]V_{2} \ = \ \displaystyle\frac{V_{1} \ \times \ T_{2}}{T_{1}} \\ \\ V_{2} \ = \ \displaystyle\frac{33.4 \ \mathrm{L} \ \times \ 339 \ \mathrm{K}}{295 \ \mathrm{K}} \\ \\ V_{2} \ = \ 38.38 \ \mathrm{L}[/tex].

Van der Waals bonds initiate
a) Between non-metals
b) Within ionic binds
c) Between metals
d) With H-bond
e) All of the above​

Answers

I think e no

I am giving you hint

Which element on the periodic table is the lowest mass in period 4??

Answers

Answer:

potassium I believe is the correct answer

Explanation:

Potassium is the period four element with the lowest mass; its average mass is 39.0983amu.

The fourth period of the periodic table is where potassium has its lowest atomic mass.

What is atomic mass?

Atomic mass is defined as the combined mass of an atom's protons, neutrons, and electrons.  The term "atomic mass" refers to the weight of an atom or molecule. To determine the average mass of elements and molecules as well as to resolve stoichiometry issues, the atomic mass is used.

An electrically neutral atom has an equal number of protons and electrons. As a result, using any of the two formulas, we may calculate the atomic mass of an element. The atomic mass of an element grows as we move from left to right in a period of the periodic table. In the fourth period of the current periodic table, Krypton has the highest atomic mass and potassium has the lowest.

Thus, the fourth period of the periodic table is where potassium has its lowest atomic mass.

To learn more about atomic mass, refer to the link below:

https://brainly.com/question/17067547

#SPJ2

Other Questions
what is an example of power shared by the federal and state governments What are the two main types of software Which inequality is graphed on the number line? what purpose has the great wall had in past and present china? Going too far beyond what the body can handle with vigorous exercise, especially without taking time to build up to the level of exercise, is an example of __________. A. Overuse B. Overexertion C. Incorrect technique D. Determination Please select the best answer from the choices provided. A B C D. 3/2 x 4/3 x 5/4 x 2006/2005 You would like to offer gifts of nominal value to potential enrollees who call for more information about a plan you represent. You would then like to offer additional gifts if they come to a marketing event. Each of the gifts meets the CMS definition of nominal value, but together, the gifts are more than the nominal value. Is this permissible? a chemical reaction in which bonds are broken is usually associated with f(x)=2x-3 for f(x)=9 The British East India Company first gained control over India through the policy of . India became a direct colony of Britain after the suppression of the in 1857. Many people in India began to resent the British and formed nationalist groups to gain . A spherical solid, centered at the origin, has radius 4 and mass density(x,y,z)=6-(x^2+y^2+z^2). Set up the triple integral and find its mass.I've attached a photo of the question. The histories of the peasants in medieval Europe, the Africans in the New World, and the native population in colonial Latin America are similar in that each group The histories of the peasants in medieval Europe, the Africans in the New World, and the native population in colonial Latin America are similar in that each group 1. was socially mobile 2. had little or no political power 3. successfully revolted against rulers 4.used political power to improve living conditions Write these numbers from least to greatest 0.152 0.152 0.132 0.140 01212 0.1412 0.150 0.148 What is the following simplified product? Assume x 0.(sqrt6x^2+4sqrt8x^3)(sqrt9x-xsqrt5x^5) Which decimals round to 2.5 when rounding to the nearest tenth What another number is divider to pi 3.14 what ear structure vibrates back and forth when sound waves strike? How is the president able to limit, or check, the power of the legislativebranch? James believes in the principals taught in the religion of Islam, which include practices such as helping the poor, praying daily, and fasting once each year for an entiremonth. These practices represent James' Need answer to the question in the picture above