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
Katena32 [7]
3 years ago
8

If 250.0 g of water at 30.0 °C cool to 5.0 °C, how many kilojoules of energy did the water lose?

Chemistry
1 answer:
Y_Kistochka [10]3 years ago
5 0

Answer:

-26.125 kj

Explanation:

Given data:

Mass of water = 250.0 g

Initial temperature = 30.0°C

Final temperature = 5.0°C

Amount of energy lost = ?

Solution:

Formula:

Q = m.c. ΔT

Q = amount of heat absorbed or released

m = mass of given substance

c = specific heat capacity of substance

ΔT = change in temperature

ΔT = T2 - T1

ΔT = 5.0°C - 30.0°C

ΔT = -25°C

Specific heat of water is 4.18 j/g.°C

Now we will put the values in formula.

Q = m.c. ΔT

Q = 250.0 g × 4.18 j/g.°C × -25°C

Q = -26125 j

J to kJ

-26125 j ×1 kj /1000 j

-26.125 kj

You might be interested in
Please help me!! 70 points!!
ICE Princess25 [194]
Do all substances dissolve in water? Kids explore the varying levels of solubility of common household substances in this fun-filled experiment!

Materials Needed:
4 clear, glass jars filled with plain tap water
Flour
Salt
Talcum or baby powder
Granulated sugar
Stirrer
Step 1: Help your child form a big question before starting the experiment.

Step 2: Make a hypothesis for each substance. Perhaps the salt will dissolve because your child has watched you dissolve salt or sugar in water when cooking. Maybe the baby powder will not dissolve because of its powdery texture. Help your child write down his or her predictions.

Step 3: Scoop a teaspoon of each substance in the jars, only adding one substance per jar. Stir it up!

Step 4: Observe whether or not each substance dissolves and record the findings!

Your child will likely note that that sugar and salt dissolve, while the flour will partially dissolve, and the baby powder will remain intact. The grainy crystals of the sugar and salt are easily dissolved in water, but the dry, powdery substances are likely to clump up or remain at the bottom of the jar.

As you can see, the scientific method is easy to work into your child’s scientific experiments. Not only does it increase your child’s scientific learning and critical thinking skills, but it sparks curiosity and motivates kids as they learn to ask questions and prove their ideas! Get started today with the above ideas, and bring the scientific method home to your child during your next exciting science experiment
7 0
3 years ago
needs help in coming up with a title for her science project. Problem statement is Do flowers last longer in the water with suga
nikdorinn [45]
Flower and sugar
flowers in sugar water? something along these lines
7 0
3 years ago
Ill give u brainliest if u help asap
UkoKoshka [18]

Radio waves, radios

microwaves, microwaves

Infrared, tv remotes

5 0
3 years ago
Sodium reacts with chlorine gas according to the following reaction: 2Na(s)+Cl2(g)→2NaCl(s) What volume of Cl2 gas, measured at
asambeis [7]

Answer:6.719Litres of Cl2 gas.

Explanation:According to eqn of rxn

2Na +Cl2=2NaCl

P=689torr=689/760=0.91atm

T=39°C+273=312K

according to stoichiometry of the reaction,1Moles of Cl2 gives 2moles of NaCl

But 28g of NaCl was given,we have to convert this to moles by using the relation, n=mass/MW

MW of NaCl=23+35.5=58.5g/mol

n=28g(mass given of NaCl)/58.5

n=0.479moles of NaCl

Going back to the reaction,

if 1moles of Cl2 produces 2moles of NaCl

x moles of Cl2 will give 0.479moles of NaCl.

x=0.479*1/2

x=0.239moles of Cl2.

To find the volume, we use ideal ggas eqn,PV=nRT

V=nRT/P

V=0.239*0.082*312/0.91

V=6.719Litres

6 0
3 years ago
PLEASE HURRY I'M TIMED
cricket20 [7]
You should give a picture of the fable!
5 0
2 years ago
Other questions:
  • Which statement describes the general trends in electronegativity and metallic properties as the elements in Period 2 are consid
    13·1 answer
  • Which acid is the best choice to create a buffer with ph= 3.19?
    9·1 answer
  • What is the molar mass of copper(II)nitrate
    5·2 answers
  • Hellpppppp pls it’s due in less than 10 min
    6·2 answers
  • Drag the tiles to the correct locations. Each tile can be used more than once, but not all tiles will be used. One or more locat
    8·2 answers
  • Estimate the heat released when ethene (CH2=CH2) reacts with HBr to give CH3CH2Br.
    6·1 answer
  • The price of tomatoes is 1.8 lb/$. How many $ would you need to buy 8.1 lb?​
    12·1 answer
  • I have 7 more questions left :’)
    14·2 answers
  • For work to be done on an object:
    13·1 answer
  • What is the molarity of a sodium hydroxide solution containing 2 moles of NaOH with a volume of .5L?
    12·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!