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3 years ago

What sort of evidence would support at least one of the components of the

Chemistry

1 answer:

Yuki888 [10]3 years ago

8 0

Answer:

(not sure) The origin of all cells observed can be traced to previous cells

Explanation:

- not all cells convert energy (?) (this I'm not sure but think so? might be wrong tho)

- not all cells have cell walls e.g. animal cells only have the cell membrane, no cell wall

- Rocks and other nonliving things are composed of cells: non living things are composed of the elements and not cells (unless they were previously alive, then they contain dead cells)

You might be interested in

When hno2 dissociates in water, which atom is dontaing electrons, allowing water to act as a lewis base?

miss Akunina [59]

Answer to this is O-atom.

Explanation: The Bronsted acid-base theory is the backbone of chemistry. This theory focuses mainly on acids and bases acting as proton donors or proton acceptors.

$A^+ + B^- \rightarrow A-B$

where $A^+$ is the Lewis Acid and $B^-$ is the Lewis Base and $A-B$ is the Covalent Bond.

Reaction of dissociation of $HNO2$ in $H_2O$ is given as:

$HNO_2 + H_2O \rightarrow H_3O^+ + NO_2^-$

In this reaction O-atom has lone pair in water and therefore it accepts the proton from $HNO_2$ forming a Lewis Base.

6 0

3 years ago

Determine ΔH for the reaction CaCO3 → CaO + CO2 given these data: 2 Ca + 2 C + 3 O2 → 2 CaCO3 ΔH = −2,414 kJ C + O2 → CO2 ΔH = −

kicyunya [14]

Answer:

The ΔH for the reaction is -456.5 KJ

Explanation:

Here we want to determine ΔH for the reaction;

Mathematically;

ΔH = ΔH(product) - ΔH(reactant)

In the case of the first reaction;

ΔH = ΔH(CaO) + ΔH(CO2) - ΔH(CaCO3) ...........................(*)

From the other reactions, we can get the respective ΔH for the individual molecule in the reaction

In second reaction;

Kindly note that for elements, molecule of gases, ΔH = 0

What this means is that throughout the solution;

ΔH(Ca) = 0 KJ

ΔH(O2) = 0 KJ

ΔH(C) = 0 KJ

Thus, in writing the equation for the subsequent chemical reactions, we shall need to write and equate the overall ΔH for the reaction to that of the product alone

So in the second reaction

ΔH = 2ΔH(CaCO3)

Thus;

-2414/2 = ΔH(CaCO3)

ΔH(CaCO3) = -1,207 KJ

Moving to the third reaction, we have;

ΔH = ΔH(CO2)

Hence ΔH(CO2) = -393.5 KJ

For the last reaction;

ΔH = ΔH(CaO)

Hence ΔH(CaO) = -1270 KJ

Going back to equation *

ΔH = ΔH(CaO) + ΔH(CO2) - ΔH(CaCO3)

Using the values of the ΔH of the respective molecules given above,

ΔH = -1270 + (-393.5) - (-1207)

ΔH = -456.5 KJ

8 0

3 years ago

The growth rate is the death rate minus the birth rate these change because birth rates and

zysi [14]

Answer:

Hey there!

False. The growth rate is actually the birth rate minus the death rates.

Let me know if this helps :)

4 0

3 years ago

If 0.2 g of nitrobenzene are added to 10.9 g of naphthalene, calculate the molality of the solution. (given: molar mass of nitro

In-s [12.5K]

Molality is defined as 1 mole of a solute in 1 kg of solvent.

Molality=

$\frac{Number of moles of solute}{Mass of solvent in kg}$

Number of moles of solute, n=

$\frac{Given mass of the substance}{Molar mass of the substance}$

Given mass of the nitrobenzene=0.2 g

Molar mass of the substance= 123.06 g mol⁻¹

Number of moles of nitrobenzene,

$n= \frac{0.2 }{123.06}$

Number of moles of nitrobenzene, n= 0.0016 mol

Mass of 10.9 g of naphthalene in kg=0.0109

$Molality= \frac{0.0016}{0.0109 }$

Molality= 0.146 m

7 0

3 years ago

The equation for the formation of water from hydrogen gas and oxygen gas is 2H2+O2→2H2O.

inn [45]

Answer:

180g

Explanation:

H:1 O:16

2H2+O2 → 2H2O

2 2(16) 2(1)+(16)

32 18

Now,

32g of O → 2(18)g of H2O

160g of O → 2(18)g divides by 32g times 160g

=180g

5 0

2 years ago