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
ExtremeBDS [4]
3 years ago
9

Is it true or false I need help.

Chemistry
1 answer:
dsp733 years ago
4 0

Answer:

true

Explanation:

You might be interested in
When 15.3 g of sodium nitrate, NaNO3,was dissolved in water in a calorimeter, the temperature fell from 25.00oC to 21.56oC. If t
satela [25.4K]

Answer:

20.468 kilo Joules is the enthalpy change when one mole of sodium nitrate dissolves.

Explanation:

Heat lost by solution ad calorimeter = Q

Heat capacity of solution ad calorimeter = C = 1071 J/°C

Change in temperature = ΔT = 21.56°C - 25.00°C = -3.44°C

Q=C\times Delta T

Q=1071 J/^oC\times (-3.44^oC)=-3,684.24 J

Heat gained by sodium nitrate = -Q = -(-3,684.24 J)=3,684.24 J

Moles of sodium nitrate = \frac{15.3 g}{85 g/mol}=0.18 mol

When 0.18 mole of sodium nitrate was dissolved in water 3,684.24 joulesof heat was absorbed by it.

Then heat absorbed by 1 mole of sodium nitrate :

\frac{3,684.24 J}{0.18}=20,468 J=20.468 kJ

1 J = 0.001 kJ

20.468 kilo Joules is the enthalpy change when one mole of sodium nitrate dissolves.

8 0
3 years ago
Hot water enters a double-pipe counter-flow water-to-oil heat exchanger at 220°7 and leaves a 100°F. Oil enters at 70°F and leav
il63 [147K]

Answer:

Oil has the smaller heat capacity. The effectiveness of the heat exchanger is 0.80.

Explanation:

Part 1:

In order to know which fluid has the smaller heat capacity we need to consider the heat equation below:

Q = CΔT, where Q is the heat exchanged, C is the heat capacity and ΔT is the variation in temperature.

As the heat exchange is the same for both fluids, the smaller the temperature variation, the smaller the heat capacity.

Water: ΔT = 120 °F  

Oil: ΔT = 80 °F  

Therefore, oil is the fluid with the smallest heat capacity.

Part 2:

The effectiveness of a counter-flow heat exchanger is given by the equation bellow:

E = \frac{Th1 - Th2}{Th1 - Tc1} \\

Th1: initial temperature of the hot fluid

Th2: final temperature of the hot

Tc1: initial temperature of the cold fluid

E = \frac{220 - 100}{220 - 70} \\E = 0.8

7 0
3 years ago
Applications of chemistry in medical field
OLga [1]

Answer:

Explanation:

Drug for the treatment of disease. Chemistry contributes to the preparation and use of materials for surgery (sutures, artificial skin, and sterile materials). ...

Surgical procedure. ...

Blood samples for laboratory testing. ...

Blood glucose testing device.

6 0
2 years ago
Density,mass,volume: Is the amount of matter a substance has
LuckyWell [14K]
Density is the mass of a substance per unit volume. Volume is the amount of space an object occupies. Chemical properties- These are properties that can only be observed by changing the identity of the substance

Hope it helped ya out!
5 0
3 years ago
A rocket travels 4500 meters in 150 seconds. What is its average speed?
Dmitrij [34]

Answer:

Your average speed was 3.77 Miles per hour

Explanation:

5 0
2 years ago
Other questions:
  • Red or irritated eyes and skin, choking, vomiting, convulsions or seizures, pinpoint pupils may be symptoms of what type of CBRN
    8·1 answer
  • Electrolysis can be used for all of the following, except A. separating metals from ores. B. plating objects with metal coatings
    9·1 answer
  • According to the phase diagram for water, how is the state of water determined?
    11·2 answers
  • What changes in color occur when bromine reacts with an alkene​
    8·1 answer
  • So I am lost and I don't know how what any of those conversion factor things are and I'm wondering how to do #2,3, and 4. (I did
    14·1 answer
  • What are the non-living things that make up an ecosystem?
    11·2 answers
  • The information below describes a redox reaction.
    10·1 answer
  • Which term refers to the loss of fertile soil from drying out?
    8·2 answers
  • What mass of KNO, will dissolve in 100 g of water at 100°C?
    11·1 answer
  • With a gas station on almost every corner, it’s hard to imagine life without fossil fuels. Fossil fuels power everything from ho
    15·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!