What energy transfer and transformation occurs when riding a bicycle?

The density of air under ordinary conditions at 25 degrees * C is 1.19g / L . How many kilograms of air are in a room that measu

professor190 [17]

Answer:

33.3 kg of air

Explanation:

This is a problem of conversion unit.

Density is mass / volume

Therefore we have to calculate the volume in the room, to be multiply by density. That answer will be the mass of air.

Volume of the room → 9 ft . 11 ft . 10 ft = 990 ft³

Density is in g/L, therefore we have to convert the ft³ to dm³ (1 dm³ = 1L)

990 ft³ . 28.3 dm³ / 1ft³ = 28017 dm³ → 28017 L

This is the volume of the room, if we replace it in the density formula we can know the mass of air in g.

1.19 g/L = Mass of air / 28017 L

Mass of air = 28017 L . 1.19 g/L → 33340 g of air

Finally, let's convert the mass in g to kg → 33340 g . 1kg / 1000 g = 33.3 kg

5 0

3 years ago

What was the purpose of letting the transformed cells sit in LB for a few minutes before spreading them onto the plates?

AlekseyPX

I think c ... C this is the correct

8 0

3 years ago

How many moles of hydrogen gas will be produced when 12 g of Mg will react completely with excess of an acid according to the fo

lina2011 [118]

Answer:

0.49 mol

Explanation:

Step 1: Write the balanced equation

Mg + 2 HCI ⇒ MgCl₂ + H₂

Step 2: Calculate the moles corresponding to 12 g of Mg

The molar mass of Mg is 24.31 g/mol.

$12g \times \frac{1mol}{24.31g} = 0.49mol$

Step 3: Calculate the moles of H₂ produced by 0.49 moles of Mg

The molar ratio of Mg to H₂ is 1:1. The moles of H₂ produced are 1/1 × 0.49 mol = 0.49 mol.

7 0

3 years ago

List at least three scientific disciplines related to chemistry mentioned or alluded to in the article. The Ozone Hole

SVETLANKA909090 [29]

Answer: biology, climate Science, astronomy etc.

Explanation:

The scientific disciplines that are related to chemistry mentioned or alluded to in the article are:

• Biology: Biology is a natural science which studies living organisms, and this include their molecular interactions, evolution, physical structure, and chemical processes.

• Astronomy: Astronomy is the study of space, and the universe. In astronomy, the stars, planets, and galaxies are all studied.

• Climate science: Climate science is also referred to as climatology and it's the scientific study of climate.

7 0

3 years ago

Bromine reacts with nitric oxide to form nitrosyl bromide as shown in this reaction: br2(g) + 2 no(g) → 2 nobr(g) a possible mec

Svetach [21]

The overall reaction is given by:

$Br_{2}(g) + 2 NO(g) \rightarrow 2 NOBr(g)$

The fast step reaction is given as:

$NO(g) + Br_{2}(g) \rightleftharpoons NOBr_{2}(g) (fast; k_{eq}= \frac{k_{1}}{k_{-1}})$

The slow step reaction is given as:

$NOBr_{2}(g) + NO(g) \rightarrow 2 NOBr(g)$ (slow step $k_{2}$ )

Now, the expression for the rate of reaction of fast reaction is:

$r_{1}=k_{1}[NO][Br_{2}]-k_{-1}[NOBr_{2}]$

The expression for the rate of reaction of slow reaction is:

$r_{2}=k_{2}[NOBr_{2}] [NO]$

Slow step is the rate determining step. Thus, the overall rate of formation is the rate of formation of slow reaction as $[NOBr_{2}]$ takes place in this reaction.