What should be done if a spectrophotometer reports an absorbance that is too high? Select one: Reposition the cuvette in the spectrophotometer. Pour out half the volume of the sample. Restart the spectrophotometer and try again. Dilute the sample. g

Answer:

C

Explanation:

Think of 'exo' as exit and 'thermic' as relating to thermal energy/ heat. Thus, an exothermic release thermal energy as the reaction proceeds.

In an exothermic reaction, the total energy of the products is lesser than that of the reactants and ΔH (change in energy) is less than zero.

When heat is absorbed as the reaction proceeds, the chemical reaction is an endothermic reaction.

Answer:

Li(s) + H2O(l) -----> LiOH(aq) + H2(g)

Ca(s) + 2H2O(l) ---------------> Ca(OH)2(aq) + H2(g)

Explanation:

Metals react with water to yield the metal hydroxide and hydrogen gas as shown in the answer above.

The reaction equations were balanced, the number of atoms of each element on both side of the reaction equation is exactly the same.

This is the way to write a balanced reaction equation for the species shown in the question.

Answer:

liquid junction potentials

when a cell contains a boundary between two electrolytic solutions of different composition or concentration, a liquid junction potential is developed due to the "diffusion of the various components at characteristic rates in the boundary zone."

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Answer:

The formula of Al³⁺ and SO₄²⁻ is aluminum sulfate.

Explanation:

The formula for aluminum sulfate is Al₂(SO₄)₃. If we say in terms of ions. The ions are Al³⁺. It is a positive ion or the cation. Other ion is SO₄²⁻. It is sulfate ion. It is anion.

Aluminum sulphate is used in water purification and as a mordant in dyeing and printing textiles.

Hence, the formula of Al³⁺ and SO₄²⁻ is aluminum sulfate.

Answer: A mass of 0.518 g of phenol must be dissolved in 25.0 g of naphthalene to produce a solution that is 0.22 m in phenol.

Explanation:

Given: Mass of naphthalene = 25.0 g

Molality = 0.22 m

This means that 0.22 moles of solute is present per kg of solvent.

As 25.0 g  of naphthalene is there that will be 25.0 g per 1000 g (1 kg) is equal to 0.025 kg.

Hence, moles of phenol are calculated as follows.

[tex]Molality = \frac{moles}{mass (in kg)}\\0.22 m = \frac{moles}{0.025 kg}\\moles = 0.0055 mol[/tex]

Also, molar mass of phenol is 94.11 g/mol. This means that 1 mole of phenol contains 94.11 g.

Therefore, mass contained by 0.0055 moles of phenol is as follows.

[tex]0.0055 mol \times 94.11 g/mol \\= 0.518 g[/tex]

Thus, we can conclude that a mass of 0.518 g of phenol must be dissolved in 25.0 g of naphthalene to produce a solution that is 0.22 m in phenol.

Answer: It is true about the type of reaction that it is a single replacement reaction, and the cations in the two ionic compounds are different.

Explanation:

When one element in a compound is replaced by another element in a chemical reaction then it is called a single replacement reaction.

For example, [tex]K + NaCl \rightarrow KCl + Na[/tex]

Here, potassium metal is replacing the sodium metal in the sodium chloride compound.

As metals become cation by losing an electron in a chemical reaction.

Thus, we can conclude that it is true about the type of reaction that it is a single replacement reaction, and the cations in the two ionic compounds are different.

Answer: Its A

Explanation:

a single replacement reactions, and the ANIONS in the two ionic compounds are different

Answer:

A. the Law of Multiple Properties

Answer:

A. the law of multiple proportions

Answer:

i believe its A, potassium iodide in water

Explanation:

Answer:

The answer is growth rate

Explanation:

it will help you

Answer:

Certain ketones such as fructose can be oxidized by Benedict's reagent under basic conditions to form what type of compound

Explanation:

Benedict's solution is a mixture of copper sulfate, anhydrous sodium carbonate, and sodium citrate.

In presence of mild reducing agents, Cu(II) ion in Benedict's solution becomes the Cu(I) ion.

Fructose has an alpha-hydroxy ketone group.

It undergoes tautomerism and forms alpha-hydroxy aldehyde which gives a positive test with Benedict's reagent.

During this test, aldehydes will be converted into carboxylic acids.

The reaction of fructose with Benedict's reagent is shown below:

Answer:

joib

Explanation:

Answer:

a

Explanation:

documentary is best researcher!.

the answer to the question is B.UV-B

Explanation:

[tex]here \: is \: your \: explanation : - \\ \\ given \: balanced \:equation \: = > \\ \\ 2 A=>C \: + \: 4D \\ \\ by \: this \: equation \: we \: get \: \\ \\ 2 \: moles \: of \: A \: produce \: 4 \: moles \: \\ \\ of \: D \\ \\ hence \: . \: 1 \: mole \: can \: produce \: = 4 \div 2 \\ \\ = > 2 \: moles \: \\ \\ so \: if \: 6 \: moles \: of \: A \: used \: then \: \\ \\ amount \: of \: D \: produced \: = (6 \times 2) \\ \\ = > 12 \: moles \: of \: D \\ \\ \mathcal\blue{ Hope \: it \: helps \: you \: (. ❛ ᴗ ❛.) }[/tex]

Answer:

mainly metal oxide use to react with both acid and bases to form salts such as zinc, aluminum etc.

Complete question:

What mass of steam initially at 120 ⁰C is needed to warm 200g of water in a 100 g glass container from 20.0 oC to 50.0 ⁰C

Answer:

the initial mass of the steam is 10.82 g

Explanation:

Given;

mass of water, m₁ = 200 g

mass of the glass, m₂ = 100 g

temperature of the steam = 120 ⁰C

initial temperature of the water, 20⁰ C

final temperature of the water, = 50⁰ C

let the mass of the steam = m

specific heat capacity of water c = 1 cal/g ⁰ C

specific heat capacity of glass c₂ = 0.2 cal/g ⁰ C

laten heat of vaporization of steam L = 540 cal/g

Apply principle of conservation energy;

Heat given off by the steam = Heat absorbed by water + heat absorbed by glass

[tex]mc\Delta T_1 + mL + mc\Delta T_2 = m_1c\Delta T_3 + m_2c_2\Delta T_3\\\\mc\Delta T_1 + mL + mc\Delta T_2 = [m_1c + m_2c_2]\Delta T_3[/tex]

m(1) (120 - 100)  +  m(540)  + m(1) (100 - 50) = [200(1)  +  100(0.2)] (50 - 20)

20m + 540m + 50m = 6600

610 m = 6600

m = 6600 / 610

m = 10.82 g

Therefore, the initial mass of the steam is 10.82 g

Answer:

C2H3O2

Explanation:

Empirical formula is defined as the simplest whole-number ratio of atoms present in a molecule. To solve this question we need to convert the percentage of each atom to moles using molar mass. With the moles of each atom we can find the ratio:

Moles C -Molar mass: 12.01g/mol-

40.68g * (1mol/12.01g) = 3.387 moles C

Moles H-Molar mass:1g/mol-:

5.12g * (1mol/1g) = 5.12 moles H

Moles O -Molar mass: 16g/mol-

54.19g * (1mol/16g) = 3.387 moles O

Ratio of atoms (Dividing in moles of C that are the lower number of moles):

C = 3.387 moles C / 3.387moles C = 1

H = 5.12moles H / 3.387moles C = 1.5

O = 3.387moles O / 3.387 moles C = 1

This ratio twice (To have only whole-numbers):

C = 2

H = 3

O = 2

Empirical formula of succinic acid:

Answer:

A = 65.46 u

Explanation:

Given that,

The composition of zinc is as follows :

Zn-64 = 48.63%

Zn-66 = 27.90%

Zn-67 = 4.10%

Zn-68 = 18.75%

Zn-70 = .62%

We need to find the  average atomic mass of the given element. It can be solved as follows :

[tex]A=\dfrac{48.63\times 64+27.90\times 66+4.1\times 67+18.75\times 68+0.62\times 70}{100}\\A=65.46\ u[/tex]

So, the average atomic mass of zinc is 65.46 u.

Answer:

Explanation:

The reaction is

H3Po4+3NH3\to→ (NH4)3PO4

Given,7.10g NH3=7.10g/molar mass of NH3

=7.10g/(17.031g/mol)

=0.416mol

From the reaction

3 mol ammonia reacted and produced 1 mole of ammoniam phosphate

So,One mole ammonia reacted and produced 1/ 3 mole ammonium phosphate.

And Also,0.416 mole ammonium reacted and produced (1/3)0.416=0.138 mole ammonium phosphate.

Hence 0.138mole=0.138mole*149.08 g/mole

               =20.573gm ammonium phosphate produced.

Hence 20.573g of ammonium phosphate is produced by the reaction of 7.10 g of ammonia.

Answer:

a. Na+ is pH neutral

b. Ni2+ = weak acid

c. NH4+ = Weak acid

Explanation:

To know the nature of the cation we need to find the nature of its conjugate base.

If the conjugate base of the ion is a strong base, the ion is neutral.

If the conjugate base is a weak base, the ion is a weak acid:

a. Conjugate base Na+ = NaOH

Sodium hydroxide is a strong base:

Na+ is pH neutral

b. Conjugate base Ni²⁺: Ni(OH)2 is a weak base because is not completely soluble in water. That means:

Ni2+ = weak acid

c. Conjugate base NH4+: NH4OH. Weak base:

NH4+ = Weak acid

Answer:

n = 0.0814 mol

Explanation:

Given mass, m = 35.7g

The molar mass of Tin(IV) bromate, M = 438.33 g/mol

We need to find the number of moles of bromine. We know that,

No. of moles = given mass/molar mass

So,

[tex]n=\dfrac{35.7}{438.33}\\\\n=0.0814\ mol[/tex]

So, there are 0.0814 moles of bromine in 35.7g of  Tin(IV) bromate.

Answer:

First, the number of ammonium sulfide molecules should be calculated:

N = NA × n,

where NA - the Avogadro number, n - number of moles.

N (ammonium sulfide) = 6.022 × 1023 × 8.5 mol = 51.187 × 1023.

The moelcular formula of ammonium sulfide is (NH4)2S. It means that each molecule contains 8 hydrogen atoms.

As a result, 8.5 mol of (NH4)2S contain:

51.187 × 1023 × 8 = 41 × 1024 hydrogen atoms.

Answer: 41 × 1024 hydrogen atoms

Answer:

As either mass increases, the gravitational force between them

increases.

Explanation:

According to Newton's law of universal gravitation;

F α m1m2/r^2

That is, the force between two masses in a gravitational field is directly proportional to the product of the two masses and inversely proportional to their distance apart.

Hence, as either of the masses increase, the force of gravitation between the two masses increases. Hence the answer.

Answer:

See explanation

Explanation:

The chlorination of benzene occurs in the presence of a Lewis acid. A Lewis acid is a compound that can accept a lone pair of electrons.

The first step in the chlorination of benzene is the formation of the ion Cl^+ which attacks the benzene ring.

This ion is formed when the Cl2 molecule undergoes heterolytic fission assisted by FeCl3 to yield FeCl4^- and Cl^+.

The Cl^+ electrophile now attacks the benzene ring to yield chlorobenzene.

Answer:

Hydrogen bonding - London dispersion forces - dipole-dipole interactions

Strongest ----> Weakest

Answer:

to the right (products side)

Explanation:

The equilibrium constant K describes the ratio between the concentration of products and reactants at equilibrium. For a general reaction:

a A + b B → c C + d D

The equilibrium constant expression is:

[tex]K = \frac{[C]^{c} [D]^{d} }{[A]^{a} [B]^{b} }[/tex]

A low value of K indicates that the concentration of products (C and D) is low in relation with the concentration of reactants (A and B).

Conversely, a high value of K indicated that the concentration of products is high compared with the concentration of reactants.

Since K = 6.4 × 10⁹ is a high value, the concentration of products is higher than the concentration of reactants at equilibrium. Thus, the position of the equilibrium is favored to the right.

Answer:

When this equation is solved, the two values of the unknown are 0.0643 and -0.082

Explanation:

Given

[tex]1.77 * 10^{-2} = \frac{x^2}{0.298 - x}[/tex] --- the actual equation

Required

The values of x

We have:

[tex]1.77 * 10^{-2} = \frac{x^2}{0.298 - x}[/tex]

Cross Multiply

[tex]1.77 * 10^{-2} * (0.298 - x)= x^2[/tex]

Multiply both sides by 100

[tex]1.77 * (0.298 - x)= 100x^2[/tex]

Open bracket

[tex]0.52746 - 1.77x= 100x^2[/tex]

Rewrite as:

[tex]100x^2 + 1.77x - 0.52746 =0[/tex]

Using quadratic formula:

[tex]x = \frac{-b \± \sqrt{b^2 - 4ac}}{2a}[/tex]

Where:

[tex]a = 100; b = 1.77; c = -0.52746[/tex]

So, we have:

[tex]x = \frac{-1.77 \± \sqrt{1.77^2 - 4*100*- 0.52746 }}{2*100}[/tex]

[tex]x = \frac{-1.77 \± \sqrt{214.1169}}{2*100}[/tex]

[tex]x = \frac{-1.77 \± 14.63}{200}[/tex]

Split

[tex]x = \frac{-1.77 + 14.63}{200}\ or\ x = \frac{-1.77 - 14.63}{200}[/tex]

[tex]x = \frac{12.86}{200}\ or\ x = \frac{-16.40}{200}[/tex]

[tex]x = 0.0643\ or\ x = -0.082[/tex]

Answer:

"Esters are widespread in nature and are widely used in industry. In nature, fats are in general triesters derived from glycerol and fatty acids. Esters are responsible for the aroma of many fruits, including apples, durians, pears, bananas, pineapples, and strawberries."

Explanation:

Answer:

Lewis structure of polyatomic formate anion.

Explanation:

To draw Lewis structure for any chemical species,

1)Count the total number of valence electrons present in it.

This can be obtained by adding valence electrons of each constituent atom.

2)Arrange those valence electrons in such a way that each atom should attain eight electrons around it to satisfy octet theory.

The structure of formate ion and its Lewis structure are shown below:

HCOO- is the formate ion.

It has total:

1+4+6+6+1 = 18 valence electrons.

Since, hydrogen has one, carbon has four and oxygen has six valence electrons and the charge of the anion is one.

Arrange this 18 electrons in such a way that each atom should get 8 electrons around it.

Resonance structures of formate ion: