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Minchanka [31]
2 years ago
7

Lens coating are made of A.teflon B.bakelite C.melamine D.PVC

Chemistry
1 answer:
suter [353]2 years ago
5 0

Answer:

C. melamine

Explanation:

a thin coating that eliminates reflections and glare from the front and back surfaces of your lenses.

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How do the interactions that are broken in water when it is boiled compare with those broken when water is electrolyzed? Boiling
nasty-shy [4]

Answer:

Boiling water breaks intermolecular attractions and electrolysis breaks covalent bonds.

Explanation:

When water boils, hydrogen bonds are broken between adjacent water molecules. The hydrogen bond is an intermolecular bond between adjacent oxygen and hydrogen atoms of water molecules.  

During electrolysis, water dissociates in the presence of electric current. Here, ions are formed in the process. Therefore, covalent bonds are broken here.

8 0
3 years ago
Give 3 examples of conduction, radiation, and convection.
cupoosta [38]

Answer:Conduction: Touching a stove and being burned. Ice cooling down your hand

Convection: Hot air rising, cooling, and falling (convection currents)

Radiation: Heat from the sun warming your face

Explanation:

3 0
2 years ago
Read 2 more answers
Homework 1
Bond [772]

Answer:

average for silk =141"

average for cotton =96"

average for nylon = 70"

if you desire a slower falling parachute to protect the body from damage,

silk is the best

if you desire a faster falling parachute to escape enemy bullets,

nylon is the best

Explanation:

Homework 1

Problem Solving

1. Kelvin and Xavier were doing an investigation on parachutes. One of them suggested that the type of material the parachute was made from had an effect on how long it took to reach the ground. Their results are given in

the table below.

(a) Calculate the average time in seconds for each material.

Time taken for parachute to reach the ground (seconds)

MATERIAL

1st TRY

2nd TRY

3rd TRY

AVERAGE

Sik

144

140  average of 3 = 141

139

Cotton

98

96   average of 3  = 96

94

Nylon

72

68    average of 3 = 70

70

5 0
2 years ago
4. Find the pH at each of the following points in the titration of 25 mL of 0.3 M HF with 0.3 M NaOH. The Ka value is 6.6x10-4 a
yawa3891 [41]

Explanation:

Since HF is a weak acid, the use of an ICE table is required to find the pH. The question gives us the concentration of the HF.

HF+H2O⇌H3O++F−HF+H2O⇌H3O++F−

Initial0.3 M-0 M0 MChange- X-+ X+XEquilibrium0.3 - X-X MX M

Writing the information from the ICE Table in Equation form yields

6.6×10−4=x20.3−x6.6×10−4=x20.3−x

Manipulating the equation to get everything on one side yields

0=x2+6.6×10−4x−1.98×10−40=x2+6.6×10−4x−1.98×10−4

Now this information is plugged into the quadratic formula to give

x=−6.6×10−4±(6.6×10−4)2−4(1)(−1.98×10−4)−−−−−−−−−−−−−−−−−−−−−−−−−−−−√2x=−6.6×10−4±(6.6×10−4)2−4(1)(−1.98×10−4)2

The quadratic formula yields that x=0.013745 and x=-0.014405

However we can rule out x=-0.014405 because there cannot be negative concentrations. Therefore to get the pH we plug the concentration of H3O+ into the equation pH=-log(0.013745) and get pH=1.86

6 0
2 years ago
Which of the following is the term for the heaviness on something's surface that exerts a force over an area? a. force b. pressu
Elan Coil [88]

Answer:

i think the answer is pressure

3 0
2 years ago
Read 2 more answers
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