#1: Which element has the same number of energy levels as bromine (Br) and the same number of valence electrons as barium (Ba)?

A. potassium (K)

B,. beryllium (Be)

c. cadmium (Cd)

D. calcium (Ca)

The following pairs of elements would most likely exhibit similar properties:

The chemical properties and behavior of elements are determined by the their valence electrons. Elements with the same number of valence electrons will exhibit similar chemical properties.

The number of valence electrons can be determined easily from the periodic table. In the periodic table the elements are arranged in columns and rows. Columns are called the groups and the rows are the periods. From left to right, each group is numbered from 1 to 18. The group number gives information about number of valence electrons of the element:

Elements that belong to the same group have similar chemical properties.

Potassium and Lithium are both Group 1 element and have one valence electron. They are both very reactive with water. They form an alkaline solution with water.

Neon and Krypton are both Group 18 or Noble Gases. Both elements have filled valence shells with eight electrons and are very stable and quite unreactive.

Keywords: chemical properties, groups,

A computer and a concentration probe

Answer:

1 65mL

Explanation:

The best reason to use titration for monitoring the effects of acid rain on drinking water is: to determine the concentration of acid in drinking water. Option A is correct.

Titrations are a well-established quantitative analysis technique that allows scientists to accurately measure the concentration of acids or bases in a solution. This can be particularly useful in environmental chemistry, where it is important to understand the acidity of drinking water due to potential contamination from acid rain.

By applying titration methods, one can detect the exact concentration of acidic species and thus assess their impact on drinking water quality. These methodologies are reliant upon accurately determining the equivalence point, which is often indicated by a change in color for a selected pH indicator, during the titration process.

Hence, A. is the correct option.

The complete question is:

Which of the following would be the best reason to use titration for monitoring the effects of acid rain on drinking water?

A. to determine the concentration of acid in drinking water

B. to find out if the drinking water contains helpful nutrients for the body

C. to find out if there are other poisonous chemicals in the drinking water

D. to determine the molar ratio of acid to base in the drinking water

Answer: KOH

Explanation:I JUST TOOK IT

Answer:

C/boiling point

Explanation:

Fractional distillation is a process that is often employed to separate various liquids from a mixture of liquids based on the respective boiling points. As the liquid mixture is heated, the component with the lowest boiling point will vaporize first and can be separated out through a condenser.

Crude oil is a mixture of several volatile hydrocarbons each having a different boiling point. Therefore, the difference in boiling point can be used to separate them through the method of fractional distillation

The components of crude oil are separated by their boiling points during the process of large-scale fractional distillation, where each substance condenses at different levels of the fractionating column.

The components of crude oil can be separated in a refinery using a process called large-scale fractional distillation. The property that allows this separation is the different boiling points of the substances contained in crude oil. When the crude oil is heated in a fractionating column, its components vaporize at different temperatures due to their various boiling points. The vapor rises through the column until it reaches a level where the temperature is low enough for it to condense back into a liquid. The components with higher boiling points condense near the bottom of the column, where the temperature is higher, while those with lower boiling points condense higher up where the temperature is cooler.

This process results in the collection of simpler mixtures of hydrocarbons and other petroleum compounds at different levels of the column. These collected liquids are then used for various applications, such as diesel fuel, kerosene, and gasoline. Boiling point differences are essential for this separation technique, making it the correct answer (C) to the question. Density, magnetism, and physical state do not serve as the primary basis for separation in this context.

Hey there! The answer you're looking for is Helium

Here shows the list of per shell

Hydrogen

Lithium

Beryllium

Theansweris Helium

This is unnecessary

Answer: Renewable fuels derived from biological matter are called biofuels.

Explanation:

Bio fuels are the fuels which are derived from plants, algae or from the waste of animals. Unlike fossil fuels they are produced from renewable resources  which can be replenished again and again.

For example; ethanol from corns and sugarcane, green diesel from algae etc.

your answer is C. To confine a fission reaction

i just took the test

Answer:

When determining the types of chemical reactions.

Explanation:

Hello,

In this case, in order to establish the different types of chemical reactions, several experiments are carried out the determine whether a chemical reaction is synthesis, decomposition, double displacement, double displacement or combustion. Such experiments consist on the combination of different of reactants under varied conditions in order the appreciate the reaction behavior over the time, changes in color, temperature changes and formed products that suggest the type of reaction.

Once the observations are set throughout the experiments, one provides the scientific knowledge that in this case will help to differentiate such types of chemical reactions.

Best regards.

Answer: Option (C) is the correct answer.

Explanation:

In a chemical reaction equation, the number of species or molecules written on the left hand side denote reactants whereas the species or molecules written on the right hand side denote products.

For example, in the given equation, [tex]SO_{2} \rightarrow S + O_{2}[/tex]. Left hand side molecule is [tex]SO_{2}[/tex] and it is the reactant. Whereas the molecules or species on right hand side are S and [tex]O_{2}[/tex] and these are the products.

Thus, we can conclude that the product(s) in this equation would be S + O2.

Answer:

1) Variables

2) Density of the solution: mass in grams / volume in mililiters

3) Mass of NaCl: m₁

    Number of moles = mass in grams / molar mass

    ⇒ mass in grams = number of moles × molar mass

        m₁ = n₁ × MM₁

4) Number of moles of NaCl: n₁

   Molarity = number of moles / Volume of solution in liters

   M = n₁ / Vt

   ⇒ n₁ = M × Vt

5) Substitue in the equation of m₁:

   m₁ = M × Vt × MM₁

6) Substitute in the equation of density:

    d = [M × Vt × MM₁ + m₂] / (1000Vt)

7) Simplify and solve for M

Making the simplistic assumption that the dissolved NaCl(s) does not affect the volume of the solvent water means 1000Vt = V₂  

        m₂/ V₂ is the density of water: 1.00 g/mL

8) Substituting MM₁ = 58.5 g/mol

Comparing with the equation Molarity = m×density + b, you obtain:

The value of m is [tex]\boxed{{\text{1/molar mass}}\left({0.0170\;{\text{mol}}\cdot{{\text{g}}^{-1}}}\right)}[/tex] and the value of b is [tex]\boxed{{\text{mol/volume}}}[/tex].

Further Explanation:

The property is a unique feature of the substance that differentiates it from the other substances. It is classified into two types:

1. Intensive properties:

These are the properties that depend on the nature of the substance. These don't depend on the size of the system. Their values remain unaltered even if the system is further divided into a number of subsystems. Temperature, refractive index, molarity, concentration, pressure, and density are some of the examples of intensive properties.

2. Extensive properties:

These are the properties that depend on the amount of the substance. These are additive in nature when a single system is divided into many subsystems. Mass, enthalpy, volume, energy, size, weight, and length are some of the examples of extensive properties.

Density is defined as the ratio between mass and volume. Both mass and volume are the physical properties that are extensive in nature and their ratio comes out to be an intensive quantity that depends only on the nature of the substance, not on the amount of the substance. The formula to calculate the density of a substance is,

[tex]{\text{Density of substance}}\left({{\rho }}\right){\text{=}}\frac{{{\text{Mass of substance}}\left({\text{M}}\right)}}{{{\text{Volume of substance}}\left({\text{V}}\right)}}[/tex]

Molarity is a concentration term that is defined as the number of moles of solute dissolved in one litre of the solution. It is denoted by M and its unit is mol/L.

The formula to calculate the molarity of the solution is as follows:

[tex]{\text{Molarity of solution}}=\frac{{{\text{amount}}\;\left({{\text{mol}}}\right)\;{\text{of}}\;{\text{solute}}}}{{\;{\text{volume}}\left({\text{L}}\right)\;{\text{of}}\;{\text{solution}}}}[/tex]

The given expression is,

[tex]{\text{Molarity}}={\text{m}}\left({{\text{density}}}\right)+{\text{b}}[/tex]           …… (1)

Substitute the formula of given quantities in equation (1).

[tex]\frac{{{\text{mol}}}}{{{\text{Volume}}}}={\text{m}}\left({\frac{{{\text{mass}}}}{{{\text{Volume}}}}}\right)+{\text{b}}[/tex]                          …… (2)

Quantities with same units are added, subtracted, multiplied or divided. So two quantities on the right-hand side of equation (2) must have the same units and equation (2) becomes,

[tex]\frac{{{\text{mol}}}}{{{\text{Volume}}}}={\text{m}}\left({\frac{{{\text{mass}}}}{{{\text{Volume}}}}}\right)+{\text{m}}\left({\frac{{{\text{mass}}}}{{{\text{Volume}}}}}\right)[/tex]                                 …… (3)

Solve for units of m,

[tex]{\text{m}}=\frac{{{\text{mol}}}}{{{\text{mass}}}}[/tex]

Or it can be written as,

[tex]{\text{m}}=\frac{{\text{1}}}{{{\text{Molar mass}}}}[/tex]                               …… (4)

Substitute 58.5 g/mol for the molar mass of NaCl in equation (4).

[tex]\begin{aligned}{\text{m}}&=\frac{{{\text{1 mol}}}}{{{\text{58}}{\text{.5 g}}}}\\&=0.0170\;{\text{mol}}\cdot{{\text{g}}^{-1}}\\\end{aligned}[/tex]

The unit of b is equal to that of m(density). So its unit can be calculated as follows:

[tex]\begin{aligned}{\text{b}}&=\left({\frac{{{\text{mol}}}}{{{\text{mass}}}}}\right)\left({\frac{{{\text{mass}}}}{{{\text{Volume}}}}}\right)\\&=\frac{{{\text{mol}}}}{{{\text{Volume}}}}\\\end{aligned}[/tex]

Learn more:

1. Rate of chemical reaction: https://brainly.com/question/1569924

2. The main purpose of conducting experiments: https://brainly.com/question/5096428

Answer details:

Grade: Senior School

Subject: Chemistry

Chapter: Keys to studying chemistry

Keywords: Property, intensive, extensive, physical properties, chemical properties, density, substance, amount, quantity, nature, molarity, units, m, b, mol/L, mol/volume, molar mass.

Representative elements are also known as Group A elements and cover a wide range of properties in the periodic table. They do not include the transition elements, which are referred to as Group B elements.

The representative elements in the periodic table are also known as the Group A elements. These elements include Groups 1A through 8A, excluding the transition metals, which are the Group B elements. The representative elements are so named because they exhibit a wide range of physical and chemical properties, representing almost all possibilities. In contrast, Group B elements or the transition elements, have their own unique properties different from representative elements.

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Answer:

Plate tectonics refers to the plate tectonic theory. According to this theory, the earth's lithosphere is divided into many parts which are commonly known as plates. These are of two types, the continental and the oceanic crust (plate). These plates move over the less dense layer of the asthenosphere from one place to another due to the creation of convection current in the layer of the mantle. This type of current forms because of the heat energy provided from the extreme internal part of the earth. This theory was simple and universally accepted and replaced the theory of continental drift discovered by Alfred Wegener.

Answer:

chromium (Cr)

Explanation:

Final answer:

Chromium (Cr) is the transition metal among the listed elements. It falls under the first transition series in the d-block of groups 3-12 on the periodic table.

Explanation:

Among the listed elements, chromium (Cr) is a transition metal. Transition metals fall within groups 3-12 on the periodic table and include the d-block elements, which are typically divided into four transition series. Chromium is part of the first transition series.

Other elements listed such as francium (Fr), beryllium (Be), gallium (Ga), and bismuth (Bi) are not considered transition metals. Francium is an alkali metal, beryllium is an alkaline earth metal, gallium is a post-transition metal, and bismuth is considered a metalloid or post-transition metal, but not a transition metal.

Barium: 2 electrons, Sodium: 1 electron, Aluminum: 3 electrons, Oxygen: 6 electrons

The number of electrons in the highest occupied energy level can be determined by looking at the electron configuration of each element. For barium (Ba), the electron configuration is 2-8-18-18-8-2, so there are 2 electrons in the highest occupied energy level. Sodium (Na) has an electron configuration of 2-8-1, so there is 1 electron in the highest occupied energy level. Aluminum (Al) has an electron configuration of 2-8-3, so there are 3 electrons in the highest occupied energy level. Oxygen (O) has an electron configuration of 2-6, so there are 6 electrons in the highest occupied energy level.

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I am unsure if this is correct (especially since I'm very late), but here are the possible answer choices to this question:

O a pure substance

O a type of a mixture

O a pure compound

O an impure substance

The answer to this is a pure substance (1st option).

Final answer:

To obtain 10L of 11% orange juice mix, we need 6L of 15% orange juice and 4L of 5% orange juice. We determine this by setting up and solving a system of linear equations based on the total volume and desired concentration.

Explanation:

To solve the problem of mixing two concentrations of orange juice to obtain 10 liters of a 11% orange juice solution, we will set up a system of equations. Let's define x as the amount of 15% orange juice and y as the amount of 5% orange juice. The total amount of the mixture should be 10 liters, so we have:

x + y = 10 ... (1)

Next, we set up the second equation based on the concentration of orange juice. Since we want the final concentration to be 11%, we can write the following equation:

0.15x + 0.05y = 0.11(10) ... (2)

Now we solve the system of equations. Multiplying equation (2) by 100 to make the numbers easier to work with, we get:

15x + 5y = 110

From equation (1), we can express y as:

y = 10 - x

Substituting y in equation (2), we have:

15x + 5(10 - x) = 110

15x + 50 - 5x = 110

10x = 60

x = 6

Now we find y using equation (1):

y = 10 - x

y = 10 - 6

y = 4

So, we need 6L of the 15% orange juice and 4L of the 5% orange juice to get 10L of 11% orange juice.