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2 years ago

What are 2 ways microscopes have changed and improved from the 16th century to present day?

Chemistry

1 answer:

Ivan2 years ago

5 0

Answer:

Glass and lens making have improved, and electronic features for microscopes have become available

Explanation:

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At a certain temperature the rate of this reaction is first order in HI with a rate constant of 0.0632 s

kirza4 [7]

Answer:

$28.037\ \text{s}$

Explanation:

$[A]_0$ = Initial concentration = 1.28 M

$[A]$ = Final concentration = $0.17[A]_0$

k = Rate constant = 0.0632 s

t = Time taken

For first order reaction we have the relation

$kt=\ln\dfrac{[A]_0}{[A]}\\\Rightarrow t=\dfrac{\ln\dfrac{[A]_0}{[A]}}{k}\\\Rightarrow t=\dfrac{\ln\dfrac{[A]_0}{0.17[A]_0}}{0.0632}\\\Rightarrow t=28.037\ \text{s}$

Time taken to reach the required concentration would be $28.037\ \text{s}$ .

8 0

3 years ago

A gas quickly expands in an isolated environment. During the process, the gas exchanges no heat with its surroundings. The proce

AysviL [449]

Answer:

e. adiabatic process

Explanation:

Adiabatic process -

In the thermodynamic system , an adiabatic process is the one which involves no transfer of mass or heat of the substance , is referred to adiabatic process.

In this process , the temperature need not be constant ,

But only the heat is transferred into or out of the system .

Hence, from the given information of the question,.

The correct option is e. adiabatic process .

6 0

4 years ago

Please help me with this three questions

zheka24 [161]

Answer:

1. A. Thyroid Gland Function

B. detecting Blood Clots

C. Treating Cancer

2. An example would be how many are used as tracers for diagnostic purposes

3. Beneficial because it gives us ways to eleminate pests, by the sterile insect technique

Number three is kinda iffy a bit difficult to explain it may be explained better in your book.

7 0

3 years ago

Laurie is moving a dresser with a mass of 250kg. She does 126 J of work with a force of 14 N. How far does she move the dresser?

babunello [35]

9m is the answer to your question

7 0

3 years ago

f 65mL of sulfuric acid and 25mL of sodium hydroxide were mixed and the solution had a density of 1.01g/mL, what is the heat of

user100 [1]

The question is incomplete, here is the complete question:

If 65 mL of sulfuric acid and 25 mL of sodium hydroxide were mixed and the solution had a density of 1.01 g/mL, What is the heat of the calorimeter in kJ given the temperature change of the above equation is -5.5 K. You may assume the solution has a heat capacity of 4.180 J/gK. Express your final answer in kJ and with 2 decimal places

Answer: The heat of the calorimeter is 2.09 kJ

Explanation:

To calculate the mass of solution, we use the equation:

$\text{Density of substance}=\frac{\text{Mass of substance}}{\text{Volume of substance}}$

Density of solution = 1.01 g/mL

Volume of solution = [65 + 25] mL = 90 mL

Putting values in above equation, we get:

$1.01g/mL=\frac{\text{Mass of solution}}{90mL}\\\\\text{Mass of solution}=(1.01g/mL\times 90mL)=90.9g$

To calculate the heat released by the reaction, we use the equation:

$q=mc\Delta T$

where,

q = heat released

m = mass of solution = 90.9 g

c = heat capacity of solution = 4.180 J/g.K

$\Delta T$ = change in temperature = -5.5 K

Putting values in above equation, we get:

$q=90.9g\times 4.180J/g.K\times (-5.5K)=-2089.8J=-2.09kJ$

Heat released by the solution will be equal to the heat absorbed by the calorimeter.

Sign convention of heat:

When heat is absorbed, the sign of heat is taken to be positive and when heat is released, the sign of heat is taken to be negative.

Heat absorbed by the calorimeter = -(-2.09) = 2.09 kJ

Hence, the heat of the calorimeter is 2.09 kJ

8 0

3 years ago