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
Genrish500 [490]
3 years ago
14

How do scientists measure the idea of time so long ago?

Chemistry
1 answer:
professor190 [17]3 years ago
6 0

The Ancient Egyptians used simple sundials and divided days into smaller parts, and it has been suggested that as early as 1,500BC, they divided the interval between sunrise and sunset into 12 parts. ... Known as a clepsydra, it uses a flow of water to measure time.

You might be interested in
When 50.0 mL of 1.00 M HCl(aq) and 50.0 mL of 1.00 M NaOH(aq) , both at 22.0 °C, are added to a coffee cup calorimeter, the temp
Igoryamba

Answer:

The heat produced by this reaction is 2887J

Explanation:

The reaction of HCl with NaOH occurs as follows:

HCl + NaOH → H2O + NaCl + ΔH

<em>Where ΔH is released heat due the reaction</em>

<em />

The equation of a coffee cup calorimeter is:

Q = C*m*ΔT

<em>Where Q is heat produced, </em>

<em>C is specific heat of the solution (4.18J/g°C), </em>

<em>m is mass of the solution (50mL + 50mL = 100mL = 100g -Because density is 1g/mL) </em>

<em>and ΔT is change in temperature (28.9°C - 22.0°C = 6.9°C)</em>

<em />

Replacing:

Q = 4.184J/g°C*100g*6.9°C

Q = 2887J

The heat produced by this reaction is 2887J

<em />

5 0
3 years ago
Why does the light coming from a flashlight appear brighter when it is closer to an object than when it is farther
Artyom0805 [142]

The answer is c and possibly a I don't know why im here i dont know what this is so bye...

8 0
3 years ago
Read 2 more answers
How much energy must be absorbed by 45.0g of water to increase its temperature from 83 0°C to 303.0°C?
mrs_skeptik [129]

Answer: There will be 41382 J energy must be absorbed by 45.0g of water to increase its temperature from 83.0^{o}C to 303.0^{o}C.

Explanation:

Given: Mass = 45.0 g

Initial temperature = 83.0^{o}C

Final temperature = 303.0^{o}C

Formula used to calculate heat energy is as follows.

q = m \times C \times (T_{2} - T_{1})

where,

q = heat energy

m = mass of substance

C = specific heat = 4.18 J/g^{o}C (here, for water)

T_{1} = initial temperature

T_{2} = final temperature

Substitute the values into above formula as follows.

q = m \times C \times (T_{2} - T_{1})\\= 45.0 g \times 4.18 J/g^{o}C \times (303.0 - 83.0)^{o}C\\= 41382 J

Thus, we can conclude that there will be 41382 J energy must be absorbed by 45.0g of water to increase its temperature from 83.0^{o}C to 303.0^{o}C.

8 0
3 years ago
Which orders the activities from the greatest to least impact to reduce consumption of fossil fuels?(1 point)
guapka [62]

Answer:

walk to work, carpool to work, drive alone to work

Explanation:

4 0
3 years ago
How many atoms are in 3.89 moles of Cu?
AleksandrR [38]

Answer:

2.34×10^24

Explanation:

N=n×Na

N=3.89×(6.02×10^23)

N=2.34×+0^24 atoms of Cu

3 0
4 years ago
Other questions:
  • Sand is made up of atoms of one kind.<br><br> True<br> False
    14·1 answer
  • Meaning of particle motion
    11·1 answer
  • Which of the following is an example of a physical change?:
    12·1 answer
  • There are two possible isomers of the product acetal that could conceivably be formed.
    7·1 answer
  • Which of the following best demonstrates kinetic energy?
    15·2 answers
  • Chemistry question. Image attached.
    13·1 answer
  • Gus is performing an experiment on cells. First he places the cells in a container of water and salt. When he checks some of the
    15·1 answer
  • If a solution contains all the solute it can hold at a given temperature, it is said to be ________________
    8·2 answers
  • How many moles of lead chloride pbCl2, will be produced if 10.0 moles of Orion chloride FeCl33 reacted
    5·1 answer
  • Can someone help me please?
    7·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!