A student makes several observations about a piece of iron. Which observation describes a chemical property of the iron?

Answer:

resend again that question dear

Answer;

P4O10 - molecular solid

Graphite - network solid

Ammonium phosphate - ionic

Brass - metallic

SiC - network solid

Rb- metallic

I2 - molecular

LiBr- ionic

P4 - molecular

Plastic - amorphous

Si - network

Explanation:

An ioinc solid is made up of a pair of oppositely charged ion held together by electrostatic interaction between the bonding species.

A covalent solid is a solid in which the atoms involved in the solid are bonded together by covalent bonds. Covalent solids are also molecular.

Metals are held together by interaction of metal ions and a sea of electrons. This is called the metallic bond.

A network solid is composed of covalently bonded atoms that repeat itself in a definite manner. E.g SiC

Answer:

Percentage yield of O₂ = 73.4%

Explanation:

We'll begin by writing the balanced equation for the reaction. This is given below:

2KClO₃ —> 2KCl + 3O₂

Next, we shall determine the mass of KClO₃ that decomposed and the mass of O₂ produced from the balanced equation. This can be obtained as follow:

Molar mass of KClO₃ = 39 + 35.5 + (3×16)

= 39 + 35.5 + 48

= 122.5 g/mol

Mass of KClO₃ from the balanced equation = 2 × 122.5 = 245 g

Molar mass of O₂ = 2 × 16 = 32 g/mol

Mass of O₂ from the balanced equation = 3 × 32 = 96 g

SUMMARY:

From the balanced equation above,

245 g of KClO₃ decomposed to produce 96 g of O₂.

Next, we shall determine the theoretical yield of O₂. This can be obtained as follow:

From the balanced equation above,

245 g of KClO₃ decomposed to produce 96 g of O₂.

Therefore, 400 g 245 g of KClO₃ will decompose to produce

= (400 × 96)/245 = 156.7 g of O₂.

Thus, the theoretical yield of O₂ is 156.7 g

Finally, we shall determine the percentage yield of O₂. This can be obtained as follow:

Actual yield of O₂ = 115.0 g

Theoretical yield of O₂ = 156.7 g

Percentage yield of O₂ =?

Percentage yield = Actual yield /Theoretical × 100

Percentage yield = 115/156.7 × 100

Percentage yield = 11500/156.7

Percentage yield of O₂ = 73.4%

Answer:

This answer I think it is Al,F

Answer: The vapor pressure of ethanol at [tex]26.3^{o}C[/tex] is 238.3 torr.

Explanation:

Given: [tex]\Delta H_{vap}[/tex] = 38.6 kJ/mol

[tex]T_{1} = 26.3^{o}C = (26.3 + 273) K = 299.3 K[/tex]

[tex]T_{2} = 78.4^{o}C = (78.4 + 273) K = 351.4 K[/tex]

Formula used to calculate the vapor pressure of ethanol is as follows.

[tex]ln\frac{P_{2}}{P_{1}} = \frac{\Delta H_{vap}}{R} [\frac{1}{T_{1}} - \frac{1}{T_{2}}]\\[/tex]

Substitute the values into above formula as follows.

[tex]ln\frac{P_{2}}{P_{1}} = \frac{\Delta H_{vap}}{R} [\frac{1}{T_{1}} - \frac{1}{T_{2}}]\\ \\ln \frac{760 torr}{P_{1}} = \frac{38600 J}{8.314 J/mol K}[\frac{1}{299.3} - \frac{1}{351.4}]\\\frac{760}{P_{1}} = 3.18\\P_{1} = 238.3 torr[/tex]

Thus, we can conclude that the vapor pressure of ethanol at [tex]26.3^{o}C[/tex] is 238.3 torr.

The required temperature of the gas sample is -64.96 °C.

Ideal gas equation gives idea about the behavior of gas at different condition & represented as:

PV = nRT.

From the above equation it is clear that relation between temperature and pressure for this question is:

P₁/T₁ = P₂/T₂, where

P₁ & T₁ are the initial pressure and temperature.

P₂ & T₂ are the final pressure and temperature.

On putting values, we get

T₂ = (145)(-25) / (55.8) = -64.96 °C

Hence required temperature of the sample is -64.96 °C.

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Answer:

Which of the following pairs lists a substance that can neutralize Ca(OH)2 and the salt that would be produced from the reaction?

HCl and CaCl2

HClO and CaHClO

H2O and Ca(OH)3

H3PO4 and Ca(PO3)2

Explanation:

The given substance is Ca(OH)2 which is a base.

To neutralise a base an acid is required.

Among the given options,

HCl and H3PO4 are the acids.

The salts foremd when calcium hydroxide reacts with the respective acids are CaCl2 and Ca3(PO4)2.

But among the given options, only the forst option that is

HCl and CaCl2 shows the correct formulas.

Hence, the answer is first option.

Answer:

HCl and CaCl2

Explanation:

Elements in the same family have the same number of protons. This  statement is not true about the periodic table. Therefore, option A is correct.

The chemical elements are arranged in rows and columns in the periodic table, sometimes referred to as the periodic table of the elements. It is frequently used in physics, chemistry, and other sciences and is frequently regarded as a symbol of chemistry.

The table can be used by scientists to anticipate chemical reactions, study trends in the periodic properties of certain elements, and speculate on the properties of yet-to-be-discovered elements. The elements are arranged in the contemporary periodic table according to their atomic numbers and periodic characteristics.

The periodic table has changed to represent more than 150 years of chemical and physics research and development.

Thus, option A is correct.

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Answer:

C.faste-moving lava flows and explosion of cinder

Answer:

This is a chemical symbol for Potassium Bromide

A chemical reaction is when reactants are converted into another substance (also called products). Their reaction rearranges the constituent atoms of the reactants to give different substances as products.

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Have a wonderful day!

Answer:

endothermic

Explanation:

endothermic reactions absorb heat from their surroundings, in this reaction the reactants are gas and solid and the products are liquid and gas, implying heat was absorbed to turn a solid to a liquid.

Answer:

Unicellular organisms consist of only one cell and multicellular organisms consist of many cell.

Explanation:

Living things made up of a cell are called unicellular beings. They are very small and simple. In other words, unicellular organisms are those that are formed only by a single cell in which all the vital functions necessary for life are produced. For this reason, they are mostly microscopic organisms. Examples of unicellular organisms are viruses or bacteria.

Multicellular organisms are made up of a large number of cells. They present, therefore, a greater complexity than unicellular organisms in terms of the functions they develop. All current multicellular organisms come from a single cell, that is, they begin their life being unicellular. That is, they are formed from a zygote. Some examples of multicellular organisms are mammals, fungi, and mosses.

So, unicellular organisms consist of only one cell and multicellular organisms consist of many cell.

Answer:

See explanation

Explanation:

Calcium carbide reacts with water to yield acetylene gas and calcium hydroxide as follows;

CaC2(s)+2H2O(g)⇋Ca(OH)2(s)+C2H2(g)

This now shows us that the equation as written in the question is wrong. Since the equation for the reaction of calcium carbide and water as shown in the question is wrong, the equation can not be balanced.

Answer:

measurements are important to do calculations to get correct results and without them scientists cannot form theories

Answer:

Glycerol;Pyruvate

Explanation:

Metabolism of triglycerides occur through a process known as lipolysis. During triglyceride metabolism, Glycerol is converted to pyruvate or glucose through glycolysis or gluconeogenesis respectively. Glycerol enters these pathways by being converted to glycerol-3-phosphate (reaction catalyzed by glycerol kinase) which can in turn be converted to dihydroxyacetone phosphate (reaction catalyzed by glycerol-3-phosphate dehydrogenase).

NOTE: Dihydroxyacetone phosphate is a compound/substrate found in both glycolysis and gluconeogenesis.

The end product of glycolysis is pyruvate; this pyruvate, under aerobic condition is converted to acetyl coA (reaction catalyzed by pyruvate dehydrogenase complex), an intermediary of the Tricarboxylic acid cycle.

Answer: the basic difference is Exergonic reactions release energy and an endergonic reactions absorb energy .

HOPE THIS HELPS!!!

Answer:

true

Explanation:

As an atom with no charge have same number of proton and electrons

Answer:

(6 mol)·(-393.5 kJ/mol) + (6 mol)·(-285.83 kJ/mol) - (1 mol)·(-1,273.02 kJ/mol) + (6 mol)·(0 kJ/mol)

Explanation:

Question; From the given options, the chemical reaction in the question is presented as follows;

C₆H₁₂O₆(s) + 6O₂(g) → 6CO₂(g) + 6H₂O(l), given that we have;

[tex]\Delta \text H _f^{\circ}[/tex] for C₆H₁₂O₆ = -1,273.02 kJ/mol

[tex]\Delta \text H _f^{\circ}[/tex] for O₂(g) = 0 kJ/mol

[tex]\Delta \text H _f^{\circ}[/tex] for CO₂(g) = -393.5 kJ/mol

[tex]\Delta \text H _f^{\circ}[/tex] for H₂O(l) = -285.83 kJ/mol

The heat or enthalpy of a reaction,  is given as follows;

[tex]\Delta\text H_{rxn}^{\circ} = \sum \text n \cdot \Delta \text H _f^{\circ}(\text {products}) - \sum \text m \cdot \Delta \text H _f^{\circ}(\text {reactants} \text)[/tex]

Therefore, the equation which should be used to calculate [tex]\Delta\text H_{rxn}^{\circ}[/tex], is given as follows;

[tex]\sum \text n \cdot \Delta \text H _f^{\circ}(\text {products})[/tex] = (6 mol)·(-393.5 kJ/mol) + (6 mol)·(-285.83 kJ/mol)

[tex]\sum \text m \cdot \Delta \text H _f^{\circ}(\text {reactants} \text)[/tex] = (1 mol)·(-1,273.02 kJ/mol) + (6 mol)·(0 kJ/mol)

Therefore;

[tex]\Delta\text H_{rxn}^{\circ}[/tex] = (6 mol)·(-393.5 kJ/mol) + (6 mol)·(-285.83 kJ/mol) - (1 mol)·(-1,273.02 kJ/mol) + (6 mol)·(0 kJ/mol)

Answer:

Clay soil

Explanation:

There are basically three types of soil namely: Sandy soil, clayey soil and loamy soil. Each of this soil type possess their own distinguishing characteristics. For example, on the basis of particle size and texture, CLAY SOIL possesses the smallest and finest particles.

Particles in a clay soil weighs lesser than 0.002 millimeters (mm) in size, making it have a high water holding or retention capacity.

Answer

Tq so much.

Pls follow me and Mark as brainliest Plsssssssss

Answer:

Thank you so much.

9.D

10.A

11.C

12.B

13.D

14.C

15.A

16.A

18.C

Answer:

3.0 mol H₂O

Explanation:

Step 1: Write the balanced combustion equation

C₂H₆ + 3.5 O₂ ⇒ 2 CO₂ + 3 H₂O

Step 2: Establish the appropriate molar ratio

The molar ratio of C₂H₆ to H₂O is 1:3.

Step 3: Calculate the moles of H₂O formed from 1.0 mole of C₂H₆

1.0 mol C₂H₆ × 3 mol H₂O/1 mol C₂H₆ = 3.0 mol H₂O

Answer:

The theoretical yield of carbon dioxide formed is 68.4 grams CO2

Explanation:

Step 1: Data given

Liquid octane = C8H18

gaseous oxygen gas = O2

gaseous carbon dioxide = CO2

gaseous water = H2O

Mass of octane = 27.4 grams

Molar mass of octane = 114.23 g/mol

Mass of oxygen = 77.8 grams

Molar mass of oxygen = 32.0 g/mol

Step 2: The reaction

2C8H18(l) + 25O2(g) → 16CO2(g) + 18H2O(g)

Step 3: Calculate number of moles

Moles = mass / molar mass

Moles of octane = 27.4 grams / 114.23 g/mol

Moles of octane = 0.240 moles

Moles of oxygen = 77.8 grams / 32.0 g/mol

Moles of oxygen = 2.43 moles

Step 4: Calculate the moles of the products

For 2 moles of octane we need 25 moles of O2 to produce 16 moles of CO2 and 18 moles H2O

O2 is the limiting reactant. It will completely react. (2.43 moles).

There will react 2.43/12.5 = 0.194 moles

There will remain 0.240 - 0.194 =  0.046 moles of octane.

There will be produced:

16/25 * 2.43 = 1.555 moles of CO2

18/25 * 2.43 = 1.750 moles of H2O

This is:

1.56 moles * 44.01 g/mol = 68.4 grams CO2

1.750 moles * 18.02 g/mol = 31.5 grams H2O

The theoretical yield of carbon dioxide formed is 68.4 grams CO2

Too lazy to draw sorry lol.

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I actually just looked it up via image search.

just copy by hand either of the flow charts.

if you can, use colors to fill. makes it more interesting to look at

and define a circle (or rather a few points on it) to draw it neatly. the defined points can later be transformed into the arrows.

Answer:

3

Explanation:

The reaction for the extraction of Iron is :-

2Fe2O3(s) + 3C(s) → 4Fe(l) + 3CO2(g)

change in oxidation state (O.S.) = higher O.S - lower O.S

= 3 - 0

= 3