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3 years ago

Which explains how burning a magnesium ribbon highlights a toolmark?

Chemistry

1 answer:

Setler [38]3 years ago

6 0

<h2>Answer:</h2>

The magnesium ribbon, <u>D. It forms a material to cast the tool mark</u>.

<h2>Explanation:</h2>

When a magnesium ribbon is burnt in the presence of oxygen it gives out strong light and heat is produced. Apart from it, it leads to the production of substance called as magnesium oxide which is formed as the product due to the reaction of magnesium with the oxygen present in the air.

Tool marks are the mark which is created by tools while using them. In order to identify or locate them castes made up of magnesium oxide is utilized. When this is pasted on the suspected area, the tool mark of the suspected tool gets pasted on it.

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Explain the difference between an organic and inorganic compound.

galben [10]

The most common differentiation to help distinguish between organic and inorganic compounds used to be the fact that organic compounds result from the activity of living beings, whereas inorganic compounds are either the result of natural processes unrelated to any life form or the result of human experimentation in the laboratory.<span><span /></span>

8 0

3 years ago

Read 2 more answers

A helium gas balloon is expanded to 78.0 L, while the pressure is held constant at 0.37 atm. If the work done on the gas mixture

Elenna [48]

Answer:

77.248 L

Explanation:

From the question,

Work done on the gas mixture is given as,

W = PΔV.................. Equation 1

Where W = work done, P = pressure of the the gas, ΔV = Change in volume of the gas.

make ΔV the subject of the equation

ΔV = W/P..................... Equation 2

Given: W = 28.2 J, P = 0.37 atm = (0.37×101325) N/m² = 37490.25 N/m²

Substitute into equation 2

ΔV = 28.2/37490.25

ΔV = 0.000752 m³

ΔV = 0.752 L

But,

ΔV = V₂-V₁................. Equation 3

Where V₂ = Final volume of the helium gas, V₁ = Initial volume of the helium gas

make V₁ the subject of the equation

V₁ = V₂-ΔV................ Equation 4

Given: V₂ = 78 L.

Substitute into equation 4

V₁ = 78-0.752

V₁ = 77.248 L

8 0

3 years ago

Read 2 more answers

Convert 163°F to kelvins.

marysya [2.9K]

Answer: 344.927778
Work: T(k)=(T(°F)+459.67)x5/9
T(K)=(60°F+459.67)x5/9=288.71 K

4 0

3 years ago

The molecular formula of a compound used for bleaching hair is H2O2. calculate (a) mass of this compound that would contain 2.5

dezoksy [38]

The RFM (Relative Formula Mass) of the substance H2O2 is:
H2 = 1 x 2
= 2
O2 = 16 x 2
= 32

32 + 2 = 34

USE THIS FORMULA:

*Mass = Moles x RFM*

Part A:

Mass = Moles x RFM
     = 2.5 x 34
   = 85 g

(You can always rearrange this formula to suit the question)

Part B:

Moles = Mass/RFM
      = 30/34
   =0.8823529........ (Need a calculator haha)
   =0.88 (Rounded up to 2 decimal places)

I hope I helped, ask if you have any questions.

4 0

3 years ago

The student diluted 50.00 mL of commercial bleaching solution to 250 mL in a volumetric flask, and titrated a 20-mL aliquot of t

Dmitriy789 [7]

To get the volume of the original solution in the dilution, we consider the dilutions that were made:

from 50 mL to 250 mL:

<span>1/5 of original was present</span>

<span>1/12.5 of the diluted mixture was presetn</span>

<span>So, V=50 mL*(1/5)*(1/12.5)= 0.8 mL of original bleaching solution was present in dilution</span>

3 0

3 years ago