What is the boiling point of gold?

Cual es la definición de las propiedades generales? ayudaaaa plis

Fantom [35]

Answer:

Son aquellas características que comparte absolutamente toda la materia, sin distinción de su composición, forma, presentación o elementos constitutivos. Las propiedades generales no permiten diferenciar una sustancia de otra. Algunas propiedades extrínsecas son la masa, el volumen, el peso y la temperatura

Explanation:

espero que esto ayude

3 0

3 years ago

A student dissolves 15.0 g of ammonium chloride(NH4Cl) in 250. 0 g of water in a well-insulated open cup. She then observes the

iren2701 [21]

Answer:

1) Endothermic.

2) $Q_{rxn}=4435.04J$

3) $\Delta _rH=15.8kJ/mol$

Explanation:

Hello there!

1) In this case, for these calorimetry problems, we can realize that since the temperature decreases the reaction is endothermic because it is absorbing heat from the solution, that is why the temperature goes from 22.00 °C to 16.0°C.

2) Now, for the total heat released by the reaction, we first need to assume that all of it is released by the solution since it is possible to assume that the calorimeter is perfectly isolated. In such a way, it is also valid to assume that the specific heat of the solution is 4.184 J/(g°C) as it is mostly water, therefore, the heat released by the reaction is:

$Q_{rxn}=-(15.0g+250.0g)*4.184\frac{J}{g\°C}(16.0-20.0)\°C\\\\ Q_{rxn}=4435.04J$

3) Finally, since the enthalpy of reaction is calculated by dividing the heat released by the reaction over the moles of the solute, in this case NH4Cl, we proceed as follows:

$\Delta _rH=\frac{ Q_{rxn}}{n}\\\\\Delta _rH= \frac{ 4435.04J}{15.0g*\frac{1mol}{53.49g} } *\frac{1kJ}{1000J} \\\\\Delta _rH=15.8kJ/mol$

Best regards!

4 0

3 years ago

Can the pH scale be utilized for all acids (Arrhenius, Bronsted-Lowery, and Lewis)? Give examples of substances from each defini

GuDViN [60]

Explanation:

Before proceeding to answering the questions, let us go over some definitions.

pH scale: The pH scale measures how acidic or basic a substance is. The pH scale ranges from 0 to 14. A pH of 7 is neutral. A pH less than 7 is acidic.

pH stands for Potential of Hydrogen. It refers to the hydrogen ion concentration in a solution.

The keywords being; Hydrogen Ion concentration.

A Bronsted-Lowry acid is a chemical species that donates one or more hydrogen ions in a reaction.

A Lewis acid is any substance that can accept a pair of nonbonding electrons. It is an electron pair acceptor.

An Arrhenius acid is a substance that dissociates in water to form hydrogen ions or protons.

Based on the definitions of given above, it is obseved that both Bronsted lowry and arrhenius acids deals with hydrogen ions. Hence both of this acids can be measured using the pH scale. The lewis acid on the other hand do not necessarily contain hydrogen ions, hence the pH scale cannot be utilized for it.

Examples includes;

Arrhenius acid; Nitric Acid – HNO3 etc

Lewis acid; boron trifluoride (BF3) and aluminum fluoride (AlF3) etc

Bronsted lowry acid; HCl etc

4 0

3 years ago

3 points

Sauron [17]

Hey there!

Elements and compounds are purely homogeneous substances and they have a constant composition throughout. Elements and compounds cannot be separated into their respective constituents by physical means. Compounds and mixtures are made up of different elements or different atoms.

7 0

3 years ago

Use atomic properties to explain the reduction of a less active metal by a more active one:(b) in the molten state. Give a speci

Bad White [126]

The reduction of a less active metal by a more active one is called metal displacement reactions. For example:

Fe + CuSO4 → FeSO4 + Cu

<h3>What is metal displacement reaction? </h3>

Displacement reactions is a reaction which includes a metal and the compound of a other metal. A more reactive metal will push or displace out a less reactive metal from its compound in this displacement reaction. The metal which is less reactive left uncombined after the reaction.

As we know that, electrons are the basis of the chemical reactions. If chemical compound or element A is more easily oxidized than B, then according to the terms of the activity series, the elements which are more easily oxidized can react with more chemicals, since they are able to act as a reducing agents for more chemicals.

Since, Metal ions are positively charged ions as they lose electrons. Some metals give up their electrons more readily than others and become more reactive.

Thus, we concluded that the reduction of a less active metal by a more active one is called metal displacement reactions. For example:

Fe + CuSO4 → FeSO4 + Cu

learn more about metal displacement reaction:

brainly.com/question/11777638

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6 0

2 years ago