The light intensity of a source is 100 candelas. The illuminance on a surface is 4 lux. How far is the surface from the source?

Answers

Answer 1

Answer: The answer is 5 meters.

The illuminance on a surface (E) is equal to the light intensity (I) divided by the square distance from the light source (d):
E = I ÷ d² [=] candela/ square meters = lux.
The unit of the illuminance is lux.

So, it is given:
E = 4 lux
I = 100 candelas
d = ?

If:
E = I ÷ d²
Then
d² = I ÷ E
⇒ d² = 100 ÷ 4
⇒ d² = 25

If we put both sides of the equation under the square root, then:
√d² = √25
⇒ d = 5 meters.

Therefore, the surface is 5 meters far from the light source.

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A certain compound is made up of one phosphorus (P) atom, three chlorine (Cl) atoms, and one oxygen (O) atom. What is the chemical formula of this compound?

Answers

Ok so we know that all of these are non metals therefore they will bond using covalent bonds.
Phoshorus can have 3 bonds Chlorine can have 1 bond and Oxygen can two bonds.
Cl-P=O
The chemical formula I belive is PClO hope this helps :).

What is the percent composition of calcium (Ca) in CaO?A 56g/40g x 100%
B 16g/56g x 100%
C 40g/56g x 100%
D 40g/100% x 56g

Answers

Answer:

C 40 g/56 g × 100 %

Explanation:

Calculate the mass of each component and the total mass.

Element Atomic mass/u No. of atoms Subtotal mass/u

Ca 40.08 1 40.08

O 16.00 1 16.00

Total = 56.08

The formula for mass percent is

% by mass = Mass of component/Total mass × 100 %

In this problem

% Ca = mass of Ca/mass of CaO × 100 %

% H = 40.08 g/56.08 g × 100 %

The percentage composition of calcium (Ca) in CaO is option C.

Here we have to determine the mass of every component and even the total mass.

Element Atomic mass/u No. of atoms Subtotal mass/u

Ca 40.08 1 40.08

O 16.00 1 16.00

Total = 56.08

The mass percent formula is

$\%\ by\ mass = Mass\ of\ component / Total\ mass * 100 \%$

$\% Ca = mass\ of\ Ca/ mass\ of\ CaO * 100 \%\n\n\% H = 40.08 g/ 56.08 g * 100 \%$

Therefore, we can conclude that the correct option is C.

Learn more: brainly.com/question/362440

Gas-to-liquid synfuel production can produce diesel, naptha and paraffin. The formation of these products usually involves _____. the Fischer-Tropsch Process the removal of carbon atoms from the fuel adding highly acidic substances such as hydrochloric acid the production of radioactive waste that must be stored in protective barrels

Answers

The best and most correct answer among the choices provided by the question is the second choice. The formation of gas-to-liquid synfuel usually involves the removal of carbon atoms from the fuel adding highly acidic substances such as hydrochloric acid. I hope my answer has come to your help. God bless and have a nice day ahead!

The formation of these products usually involves THE FISCHER-TROPSCH PROCESS.

The Fischer-Tropsch process refers to a series of chemical reactions which convert hydrogen and carbon monoxide into liquid hydrocarbons in the presence of metal catalysts. The temperature utilized in the process is normally between 150 and 300 degree Celsius. The techniques was developed by Franz Fischer and Hans Tropsch in 1925. The technique is usually used to turn coal into liquid and to turn gases to liquid fuels.

How many moles are in 1.9 x 10^25 molecules of carbon dioxide

Answers

1 mole ----------- 6.02x10²³ molecules
? moles --------- 1.9x10²⁵ molecules

moles = 1.9 x 10²⁵ * 1 / 6.02x10²³

= 1.9 x 10²⁵ / 6.02x10²³

= 31.561 moles

hope this helps!

Which type of reaction is represented by the generic equation AB + CD mc002-1.jpg AD + CB?combustion

decomposition

single replacement

double replacement

Answers

Answer : Option D) Double replacement

Explanation : Double displacement or replacement reactions are those in which the two reactant molecules exchange the cations and anions between them and give a new product.

So, in this case when the reaction is AB + CD → AD + CB

Here, both the species of reactant compound molecule went replacement with the adjacent cation and anion group and formed a new compound or product. Therefore, this can be called as double replacement reaction.

The type of reaction is represented by the generic equation AB + CD -> AD + CB is double replacement. The rest of the choices do not answer the question above.

A solution of NaOH is titrated with H2SO4. It is found that 20.05 mL of 0.3564 M H2SO4 solution is equivalent to 43.42 mL of NaOH solution. What is the concentration of NaOH?