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3 years ago

PLEASE HELP ASAP 50 POINTS!!!

2 answers:

Alex3 years ago

8 0

The atomic number of an atom is the number of A.protons An ion is an atom D. That has the same number of protons and neutrons.

Which of the following is true regarding photosynthesis and respiration? C. Photosynthesis breaks down glucose; respiration makes glucose. hope this helps

ohaa [14]3 years ago

5 0

1. The atomic number of an atom is the number of protons in the nucleus.

2. An ion is an atom that has an unequal number of protons and electrons.

3. Photosynthesis occurs in the chloroplasts; respiration occurs in the mitochondria.

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Explain why the total amount of energy does not decrease in an exergonic <br> chemical reaction

Zielflug [23.3K]

An exergonic reaction is a chemical reaction where the change in the free energy is negative (there is a net release of free energy),[1] indicating a spontaneous reaction. For processes that take place under constant pressure and temperature conditions, the Gibbs free energy is used whereas the Helmholtz energy is used for processes that take place under constant volume and temperature conditions.

Symbolically, the release of free energy, G, in an exergonic reaction (at constant pressure and temperature) is denoted as

{\displaystyle \Delta G=G_{\rm {products}}-G_{\rm {reactants}}<0.\,}

Although exergonic reactions are said to occur spontaneously, this does not imply that the reaction will take place at an observable rate. For instance, the disproportionation of hydrogen peroxide is very slow in the absence of a suitable catalyst. It has been suggested that eager would be a more intuitive term in this context.[2]

More generally, the terms exergonic and endergonic relate to the free energy change in any process, not just chemical reactions. An example of an exergonic reaction is cellular respiration. This relates to the degrees of freedom as a consequence of entropy, the temperature, and the difference in heat released or absorbed.

By contrast, the terms exothermic and endothermic relate to the overall exchange of heat during a process

4 0

3 years ago

1. What is Chemistry?

sertanlavr [38]

Answer:

study of chemicals and knowing elements shirt definition of element follow me plz....

8 0

3 years ago

Read 2 more answers

Lead(II) oxide from an ore can be reduced to elemental lead by heating in a furnace with carbon. Calculate the expected yield of

Lelu [443]

Answer:

53kg is the expected yield of lead

Explanation:

Firstly, in order to solve this question, we need to write the equation of reaction correctly. This is as follows:

PbO(s) + C(s) ---> Pb(l) + CO(g)

We proceed from here. We should get the limiting reactant but this can only be obtained by getting the number of moles of each reactant present.

The formula to use across all boards is that the number of moles is the mass of each of the reactant divided by the molar mass of each of the reactant.

For PBO, mass is 57kg = 57000g

Molar mass of PBO = 223.20g/mol

The number of moles is thus 57,000/223.2 = 255.37 moles

For carbon, mass is also 57kg = 57000g

Molar mass is 12g/mol

Number of moles of carbon = 57000/12 = 4750 moles

From the number of moles, we can see that the number of moles of Carbon is greater than that of PbO. This means that PbO is the limiting reagent.

Hence we use it to calculate percentage yield.

The number of moles of lead formed is the same of number of moles of lead oxide = 255.37 since we have mole ratio of 1 to 1

The molar mass of lead is 207.20g/mol

The mass of lead formed is = moles of lead formed * molar mass of lead = 207.20 * 255.37 = 52,912g which is approximately 53kg

Hence the expected yield is 53kg

6 0

3 years ago

What is the volume of a sample of ammonia gas (NH3) if it contains 0.23 moles?

LekaFEV [45]

The volume of a sample of ammonia gas : 5.152 L

<h3>Further explanation</h3>

Given

0.23 moles of ammonia

Required

The volume of a sample

Solution

Assumed on STP

Conditions at T 0 ° C and P 1 atm are stated by STP (Standard Temperature and Pressure). At STP, Vm is 22.4 liters / mol.

So for 0.23 moles :

= 0.23 x 22.4 L

= 5.152 L

8 0

3 years ago

Identify each of the following sets of quantum numbers as allowed or not allowed in the hydrogen atom.

Westkost [7]

Answer:

See explanation.

Explanation:

Hello there!

In this case, according to the given information, it turns out possible for us to firstly recall the electron configuration of hydrogen:

$1s^1$

To realize that the principal quantum number is 1, the angular is 0 as well as the magnetic one; therefore we infer that all the given n's are not allowed, just l=0 is allowed as well as ml=0 yet the rest, are not allowed.

Best regards!

5 0

3 years ago