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3 years ago

What is essential to living things because many of the chemical reactions that occur in living things require it?

2 answers:

6 0

Oxygen, carbon dioxide(for respiration and photosynthesis), nitrogen(needed to make proteins which in turn are needed for enzymes and hormones), hydrogen(to be combined with carbon and oxygen to make organic compounds or food for living organisms), and sunlight.

erma4kov [3.2K]3 years ago

5 0

Water because water acts as a solvent to chemical reactions. If we wouldn't have water maybe there wouldn't be any living things.

You might be interested in

How many chromosomes are present in a sex cell of a pea plant?

natta225 [31]

Answer:

14 Chromosomes

Explanation:

I looked it up. Hope it helps somewhat :)

8 0

4 years ago

Read 2 more answers

Archimedes tells us the lifting power of a balloon (how much mass it can lift) is equal to the difference between the mass of th

Finger [1]

Answer:

the Balogna could carry 19 passengers if filled with Hydrogen.

the Balogna could carry 17 passengers if filled with Helium.

Explanation:

Given that:

the radius of the cylinder r = 4.0 cm

the height h = 40 m

the volume of the cylinder will be:

$V = \pi r^2 h$

V = π (4.0 m)² (40)

V = 2010.62 m³.

where the density of the air = 1.23 kg/m³

the mass of the displaced air = Volume V ×density of the air

= 2010.62 m³ × 1.23 kg/m³

= 2473.0626 kg

To calculate how many passengers the Balogna could carry if it were filled with hydrogen, we have the following:

We are given the density of H₂ to be = 0.090 kg/m³

Therefore, the mass of Helium in the balloon = Volume V × density of the hydrogen

= 2010.62 m³ × 0.090 kg/m³

= 180.9558 kg

The total mass of the balloon = mass of H₂ + mass of empty balloon.

The total mass of the balloon = (180.9558+ 750) kg

= 930.9558 kg

Now, the Mass difference = mass of the air displaced -total mass of the balloon.

the Mass difference = (2473.0626 - 930.9558 ) kg

the Mass difference = 1542.1068 kg

∴

number of persons = mass difference/ mass of passenger

the number of persons = 1542.1068 kg /80 (kg/person)

the number of persons = 19.27 persons

the number of passengers $\simeq$ 19 passengers.

To calculate how many passengers the Balogna could carry if it were filled with helium, we have the following:

We are given the density of Helium to be = 0.18 kg/m³

Therefore, the mass of Helium in the balloon = Volume V × density of the hydrogen

= 2010.62 m³ × 0.18 kg/m³

= 361.9116 kg

The total mass of the balloon = mass of Helium + mass of empty balloon.

The total mass of the balloon = (361.9116 + 750) kg

= 1111.9116 kg

Now, the Mass difference = mass of the air displaced -total mass of the balloon.

the Mass difference = (2473.0626 - 1111.9116 ) kg

the Mass difference = 1361.151 kg

∴

number of persons = mass difference/ mass of passenger

the number of persons = 1361.151 kg /80 (kg/person)

the number of persons = 17.01 persons

the number of passengers $\simeq$ 17 passengers.

7 0

3 years ago

Find the percentage composition of a compound that contains 17.6 g of iron and

olganol [36]

Answer:

Explanation:

Your goal here is to figure out the mass of iron and the mass of sulfur present in exactly

100 g

of this compound, which is what you need in order to know the compound's percent composition.

The problem provides you with the mass of iron and with the mass of sulfur present in

27.9 g

of this compound, so you must use this information to scale up your sample from

27.9 g

100 g

To do that, set up the known composition of the compound as a conversion factor.

To find the number of grams of iron present in

100 g

of compound, set up the conversion factor like this

17.6 g iron

27.9 g compound

You will end up with

100

g compound

⋅

17.6 giron

27.9

g compound

63.1 g iron

To find the mass of sulfur present in

100 g

of compound, you can either use a conversion factor set up in a similar manner

100

g compound

⋅

10.3 g sulfur

27.9

g compound

36.9 g sulfur

or use the fact that the compound contains only iron and sulfur to say that the mass of sulfur will be equal to

100 g compound

−

63.1 g iron = 36.9 g sulfur

You now know the mass of iron and the mass of sulfur present for every

100 g

of compound, so you can say that the compound has the following percent composition

63.1% iron

36.9% sulfur

Here

means per

100 g

of compound.

5 0

3 years ago

If an insufficient amount of liquid unknown had been used, how would this have effected the value of the experimental molar mass

Effectus [21]

When the unknown liquid is heated and turned into vapor, it will not occupy the entire container. The volume in the molar mass (nRT)/PV will be greater than the actually volume of the unknown, and the calculated molar mass will be less than the actual molar mass.

5 0

4 years ago

A solution of 400mg of optically active 2-butanol in 10 mL of water, placed in a 20 cm cell shows an optical rotation of 40o. Wh

labwork [276]

Answer:

Specififc rotation [∝] = 0.5° mL/g.dm

Explanation:

Given that:

mass = 400 mg

volume = 10 mL

For a solution,

The Concentration = mass/volume

Concentration = 400/10

Concentration = 40 g/mL

The path length l = 20 cm = 2 dm

Observed rotation [∝] = + 40°

Specififc rotation [∝] = ∝/l × c

where;

l = path length

c = concentration

Specififc rotation [∝] = (40 / 2 × 40)

Specififc rotation [∝] = 0.5° mL/g.dm

3 0

3 years ago