All categories

3 years ago

A bus travels 20km in 30minutes what is the average speed of the bus?

Chemistry

1 answer:

Vera_Pavlovna [14]3 years ago

7 0

Answer:

40km/hr

Explanation:

Speed = Distance ÷ Time and since they both have different units we have to change one of them. Therefore if we change 30 minutes to half an hour we say 20km ÷ ¹/2

You might be interested in

Describe how atomic emission spectrums came about, and what they say about atoms/electrons.

algol [13]

Answer:

Atomic emission spectrum came out by a series of colored lines

Explanation:

When electricity is passing through an element or when it is viewing through a prism, a unique spectra of light emitted by an element is called atomic emission spectra. They are acting as an element of finger print because they are unique. When we are seeing a set of colored lines or a black background , it is an emission spectrum. If we are watching black lines on a colored background it is absorption spectrum. In electromagnetic spectrum the visible portion are the colors.

In nucleus electrons can exist in some areas are known as shells. Shell corresponds an energy level that is designed by a quantum number n. The lowest energy level electrons are close to the nucleus.

An atom is shone by light, its electrons absorbs photons and it gain energy, and jump to higher level.

8 0

3 years ago

A 2.4L balloon filled with helium at room temperature 25oC is put into liquid nitrogen

Stels [109]

Answer:

V₂ = 0.62 L

Explanation:

Given data:

Initial volume = 2.4 L

Initial temperature = 25°C

Final temperature = -196°C

Final volume = ?

Solution:

Initial temperature = 25°C (25+273 = 298 K)

Final temperature = -196°C ( -196+273 = 77 K)

The given problem will be solve through the Charles Law.

According to this law, The volume of given amount of a gas is directly proportional to its temperature at constant number of moles and pressure.

Mathematical expression:

V₁/T₁ = V₂/T₂

V₁ = Initial volume

T₁ = Initial temperature

V₂ = Final volume

T₂ = Final temperature

Now we will put the values in formula.

V₁/T₁ = V₂/T₂

V₂ = V₁T₂/T₁

V₂ = 2.4 L × 77 K / 298 k

V₂ = 184.8 L.K / 298 K

V₂ = 0.62 L

5 0

3 years ago

An ordered list of chemical substances is shown. Chemical Substances 1 CuO 2 O2 3 CO2 4 NO2 5 Fe 6 H2O Which substances in the l

a_sh-v [17]

Answer:

reactants: 2 O2

products: 3 CO2, 4 NO2, 6 H2O

Explanation:

In a combustion, a combustible material, which generally is composed of C, H, O, N, and S, is combusted, that is, react with oxygen after a spark was produced; obtaining fire, heat and subproducts, including ashes and gases.

Oxygen is always one of the reactants of a combustion.

If Nitrogen was present in the combustible, NO2 (or other nitrogen oxides) will be produced.

If Carbon was present in the combustible, CO2 will be produced (also CO can be produced).

If Hydrogen was present in the combustible, H2O will be produced.

7 0

3 years ago

How many moles of sodium phosphate would be required to react with 1.0 mol of silver nitrate

WITCHER [35]

1) State the balanced chemical equation

Na3 PO4 + 3 AgNO3 → 3NaNO3 + Ag3 PO4

sodium phosphate silver nitrate sodium nitrate silver phosphate

2) State the molar ratios

1 mol Na3PO4 : 3 mol AgNO3 : 3 mol NaNO3 : 1 mol Ag3 PO4

3) As you see 3 moles of Silver Nitrate react with 1 mol of Na3 PO4, then you will need.

The you need to use the molar ratio 1:3 to calculate the number of moles of sodium phosphate

1 mol Ag NO3 * [ 1 mol Na3 PO4 / 3 mol Ag NO3] = 0.33 mol Na3 PO4

Answer: 0.33 mol sodium phosphate

3 0

3 years ago

Which is the correct orbital diagram for carbon?

Brrunno [24]

Answer:

its 2p

Explanation:

In a neutral carbon atom, the 1s sublevel has one orbital with two electrons with opposite spins, represented by the arrows pointing in opposite directions. The 2s sublevel also has one orbital with two electrons, also with opposite spins. The 2p sublevel has three orbitals.

(i don"t understand this i just looked it up ._.

4 0

3 years ago