Question 1 Points 3 23 and Louis immerses his left hand in a beaker containing cold water and immerses his right hand in a beaker containing warm water. Then, he immerses both his hands on a beaker containing water at room temperature. Which of the following statements are true? 1. The hand that was in hot water would feel cold. 2. The hand that was in cold water would feel hot. 3. His two hands will feel the same hotness. Que O2 and 3 0 1 and 2 o 1 and 3 1.2, and 3​

Answer:

a)calculated molarity of NaOH would be lower

b) calculated molarity of NaOH would be lower

c) calculated molarity of NaOH would be lower

d) calculated molarity of NaOH would be unaffected

Explanation:

Let us recall that the reaction of NaOH and HCl is as follows;

NaOH(aq) + HCl(aq) ----> NaCl(aq) + H2O(l)

Since the reaction is 1:1, when the number of moles of HCl reacting with NaOH is low due to dilution, the calculated molarity of NaOH also becomes less than it's accurate value.

When 40mL of water is added to the titration flask rather than 25ml of water, the acid is more dilute hence less number of moles of acid than necessary reacts with the base thereby yielding a less than accurate value of the molarity of NaOH.

If the burette wet with water is not rinsed with NaOH solution, the concentration of the NaOH in the burette decreases due to dilution with water and a less than accuracy value is calculated for the molarity of NaOH.

If five drops of phenolphthalein is used instead of one or two drops, there is no qualms since enough phenolphthalein may be added to ensure that a sharp end point is obtained.

The formula that we can use to calculate energy released when a mass of liquid freezes is Grams liquid x mol/g x delta Hfusion.

Stoichiometry deals with the relationship between mass and moles or volume which can be used to make calculations involving chemical reactions. Most chemical calculations involving stoichiometry use the mole concept.

Hence, the formula used to obtain the energy released when a mass of liquid freezes is Grams liquid x mol/g x delta Hfusion.

Learn more about stoichiometry: https://brainly.com/question/9743981

Answer:

B.9.710-11M

Explanation:

Answer:

0.796 M

Explanation:

Step 1: Given data

Gravimetric concentration (Cg): 4.78 g%g

Density of the solution (ρ): 1.00 g/mL

Step 2: Calculate the volumetric concentration of the solution (Cv)

We will use the following expression.

Cv = Cg × ρ

Cv = 4.78 g%g × 1.00 g/mL = 4.78 g%mL

Step 3: Calculate the molarity of the solution (M)

The volumetric concentration is 4.78 g%mL, that is, there are 4.78 g of acetic acid per 100 mL of solution. We can calculate the molarity using the following expression.

M = mass solute / molar mass solute × liters of solution

M = 4.78 g / 60.05 g/mol × 0.1 L = 0.796 M

Answer:

The correct answer is "[tex]4.991\times 10^{-45} \ kg.m^2[/tex]".

Explanation:

According to the question,

[tex]R_{C-Cl} = 177 \ pm[/tex]

or,

         [tex]=1.77\times 10^{-10} \ m[/tex]

[tex]\alpha = 107^{\circ}[/tex]

[tex]m_{Cl}=34.97 \ m.u[/tex]

or,

      [tex]=34.97\times 1.66\times 10^{-27}[/tex]

      [tex]=5.807\times 10^{-26} \ kg[/tex]

The moment of inertia around the rotational axis will be:

⇒  [tex]I=3\times m_{Cl}\times (R_{C-Cl})^2 \ Sin^2 \alpha[/tex]

By putting the values, we get

       [tex]=3\times 5.807\times 10^{-26}\times (1.77\times 10^{-10})^2 \ Sin^2 (107)[/tex]

       [tex]=3\times 5.807\times 10^{-26}\times (1.77\times 10^{-10})^2\times 0.91452[/tex]

       [tex]=4.991\times 10^{-45} \ kg.m^2[/tex]

Answer:

The molar concentration of the H₂SO₄ solution is 0.28 M

Explanation:

Molar concentration = number of moles / volume in litres

Number of moles = molar concentration × volume

From the equation of reaction, molar ratio of acid to base = 1 : 2

Using the formula; Na/Nb = CaVa/CbVb

Where Na is the number of moles of acid; Nb = number of moles of base; Ca = concentration of acid; Va = volume of acid; Cb = concentration of base; Vb = volume of base; Na/Nb = mole ratio of acid to base

Substituting the given values in the equation:

1/2 = Ca × 25.18 / 0.93 × 14.92

Ca = 0.93 × 14.92/ 25.18 × 2

Ca = 0.28M

Therefore, the molar concentration of the H₂SO₄ solution is 0.28 M

Answer:

Rank the following chemical species from lowest absolute entropy (So) (1) to highest absolute entropy (5) at 298 K?

a. Al (s)

b. H2O (l)

c. HCN (g)

d. CH3COOH (l)

e. C2H6 (g)

Explanation:

Entropy is the measure of the degree of disorderness.

In solids, the entropy is very less compared to liquids and gases.

The entropy order is:

solids<liquids<gases

Among the given substances, water in liquid form has a strong intermolecular H-bond.

So, it has also less entropy.

Next acetic acid.

Between the gases, HCN, and ethane, ethane has more entropy due to very weak intermolecular interactions.

HCN has slight H-bonding in IT.

Hence, the entropy order is:

Al(s) < CH3COOH (l) <H2O(l) < HCN(g) < C2H6(g)

Answer:

There are 1.195 calories in 5 J.

Explanation:

The relation between calorie and Joules is as follow :

4.184 J = 1 calorie

or

1 J = (1/4.184) calorie

Let the taken number is 5 J

So,

5 J = (5/4.184) calorie

5 J = 1.195 calorie

So, there are 1.195 calories in 5 J.

Answer:

1.17 L of H₂

Explanation:

We'll begin by calculating the number of mole in 2.3 g of Mg. This can be obtained as follow:

Mass of Mg = 2.3 g

Molar mass of Mg = 24 g/mol

Mole of Mg =?

Mole = mass /molar mass

Mole of Mg = 2.3 / 24

Mole of Mg = 0.096 mole

Next, we shall determine the number of mole of H₂ produced by the reaction of 2.3 g (i.e 0.096 mole) of Mg. This can be obtained as follow:

Mg + 2HCl —> MgCl₂ + H₂

From the balanced equation above,

1 mole of Mg reacted to 1 mole of H₂.

Therefore, 0.096 mole of Mg will also react to produce 0.096 mole of H₂.

Finally, we shall determine volume of H₂ produced from the reaction. This can be obtained as follow:

Number of mole (n) of H₂ = 0.096 mole

Pressure (P) = 2 atm

Temperature (T) = 298 K

Gas constant (R) = 0.0821 atm.L/Kmol

Volume (V) of H₂ =?

PV = nRT

2 × V = 0.096 × 0.0821 × 298

Divide both side by 2

V = (0.096 × 0.0821 × 298) /2

V = 1.17 L

Therefore, 1.17 L of H₂ were obtained from the reaction.

Answer:

False

Explanation:

An object with a density greater than 1.00g/mL (greater than the density of water) will sink. An object with a density less than the density of water, will float.

If the water has a density of 1.00 g/mL. If you put an object that has a density of 0.79 g/mL into water, it will sink to the bottom, this statement is false.

The density of an actual content is its mass per unit volume. The most common symbol for density is d, but the Latin letter D can also be used.

Three of an object's most fundamental properties are mass, volume, and density. Mass describes how heavy something is, volume describes its size, and density is defined as mass divided by volume.

The density of something is a measure of how heavy it is in relation to its size. When an artifact is more dense than water, it plunges; when an object is less dense than water, it floats.

Density is a property of a substance that is independent of the amount of substance.

As in the given scenario, water is having density 1 g/mL and object in having density less then it so it will float on water.

Thus, the given statement is false as the material will not sink, rather it will float on water.

For more details regarding density, visit:

https://brainly.com/question/15164682

#SPJ2

Answer:

Danger

Explanation:

Answer:

hope it helps much as you can

Answer:

C₂H₆(g) + 2.5 O₂(g) ⇒ 2 CO(g) + 3 H₂O(g)

Explanation:

Let's consider the unbalanced equation in which gaseous ethane reacts with gaseous oxygen to form carbon monoxide gas and water vapor. This is an incomplete combustion reaction.

C₂H₆(g) + O₂(g) ⇒ CO(g) + H₂O(g)

We will balance it using the trial and error method.

First, we will balance C atoms by multiplying CO by 2 and H atoms by multiplying H₂O by 3.

C₂H₆(g) + O₂(g) ⇒ 2 CO(g) + 3 H₂O(g)

Then, we get the balanced equation by multiplying O₂ by 2.5.

C₂H₆(g) + 2.5 O₂(g) ⇒ 2 CO(g) + 3 H₂O(g)

Answer:

Density and rigidity

Answer:

hydrogen, oxygen, chlorine, ammonia

Explanation:

Air is a mixture of gases. When we say "clean" air here, we are referring to air that does not contain pollutant gases.

Some components of air such as water vapour, methane, CO2, and N2O are greenhouse gases. They are known to contribute towards global warming.

Some gases such as SO2 and NO2 contribute towards acid rain. The oxides of nitrogen are particularly involved in the formation of photochemical smog.

The halogens are known to lead to the depletion of the ozone layer and radon is a radioactive gas.

Hence, hydrogen, oxygen, chlorine, ammonia have no negative environmental impact hence they are found in clean air.

Answer:

Ka = 3.45x10⁻⁶

Explanation:

First we calculate [H⁺], using the given pH:

To solve this problem we can use the following formula describing a monoprotic weak acid:

We input the data that we already know:

And solve for Ka:

The electronegativity increases across the period and decreases down the group. Thus, option B is correct.

Electronegativity can be defined as the tendency of an atom to gain or attract an electron. The electronegativity has been dependent on the size of the atom, as well as the atomic number and valence electrons.

The atom with the requirement of a less number of atoms to complete its octet can easily gain the electron and thereby have high electronegativity. The atomic size also plays a role in the electronegativity of the atom.

The atom with a bigger size has the lesser force of attraction from the nucleus and thus has difficulty attracting the electron, however, the smaller size atom can easily attract the electron with the attraction force from the nucleus.

Thus, the elements with smaller sizes and a high number of valence electrons are more electronegative. In the periodic table, on moving from left to right the valence electrons increase, thus the electronegativity increases.

On moving down the group, the element size increase, thus the electronegativity decreases down the group.

The electronegativity increases across the period and decreases down the group. Thus, option B is correct.

For more information about electronegativity, refer to the link:

https://brainly.com/question/2060520

Answer:

[tex]M_{a}[/tex] = 0.104 m

Explanation:

This expression is used to determine either the mass or volume of an acid or a base used during titration process.

So that;

[tex]M_{a}[/tex][tex]V_{a}[/tex] = [tex]M_{b}[/tex][tex]V_{b}[/tex]

[tex]M_{a}[/tex] is the mass of the acid

[tex]V_{a}[/tex] is the volume of the acid

[tex]M_{b}[/tex] is the mass of the base

[tex]V_{b}[/tex] is the volume of the base

Given that:

[tex]M_{a}[/tex] x 5.0 m l = 5.2 ml x 0.10 m

[tex]M_{a}[/tex] x 5.0 = 0.52 m

[tex]M_{a}[/tex] = [tex]\frac{0.52}{5.0}[/tex]

      = 0.104

[tex]M_{a}[/tex] = 0.104 m

The mass of the acid used is 0.104 m.

Answer:

In compound 1 the Tert butyl group occupies the equatorial position and the Bromine occupies the axial position and in compound 2 the Tert butyl occupies the axial and the bromine occupies equatorial positions. Compound 1 reacts faster than compound 2.

Explanation:

In cyclic organic compounds, substituents may occupy the axial or equatorial positions. The axial positions are aligned parallel to the symmetry axis of the ring while the equatorial positions are around the plane of the ring.

Bulky substituents have more room in the equatorial than in the axial position. This means that compound 1 is more stable than compound 2.

This is clear on the basis of stability of the molecules because compound 1 will react faster than compound 2 since the bulky tertiary butyl group in compound 1 occupy equatorial and not axial positions.

Answer:

0.53atm = P2

Explanation:

Gas at 1.00atm and 20°C. Temperature increased to 40°C...

We can solve this question using combined gas law:

P1*V1 / T1 = P2*V2 / T2

Where P is pressure, V volume and T absolute temperature of 1, initial state and 2, final state.

Compunting the values of the problem:

P1 = 1.00atm

V1 = 250mL

T1 = 20°C + 273.15 = 293.15K

P2 = ?

V2 = 500mL

T2 = 40°C + 273.15 = 313.15K

1.00atm*250mL / 293.15K = P2*500mL / 313.15K

answer

j'ai besoin d'aide

=]

<3

Answer:

36.55kJ/mol

Explanation:

The heat of solution is the change in heat when the KNO3 dissolves in water:

KNO3(aq) → K+(aq) + NO3-(aq)

As the temperature decreases, the reaction is endothermic and the molar heat of solution is positive.

To solve the molar heat we need to find the moles of KNO3 dissolved and the change in heat as follows:

Moles KNO3 -Molar mass: 101.1032g/mol-

10.6g * (1mol/101.1032g) = 0.1048 moles KNO3

Change in heat:

q = m*S*ΔT

Where q is heat in J,

m is the mass of the solution: 10.6g + 251.0g = 261.6g

S is specififc heat of solution: 4.184J/g°C -Assuming is the same than pure water-

And ΔT is change in temperature: 25°C - 21.5°C = 3.5°C

q = 261.6g*4.184J/g°C*3.5°C

q = 3830.87J

Molar heat of solution:

3830.87J/0.1048 moles KNO3 =

36554J/mol =

Answer:

Human life has become very simple by using organic chemicals. The importance of organic chemicals in the daily life and industrial area can be explained as follows. (i) Food Vitamins, proteins, sugar, flour, fats etc. ... (ii) Agriculture is an important place for organic chemical for the growth of agricultural production.

Answer:

dispersion force

Explanation:

Answer:

True

Explanation:

The valence orbitals of boron are 2s2 2p1. We have to recall that all the valence orbitals whether full or empty are involved in the formation of molecular orbitals.

The number of molecular orbitals formed is equal to the number of atomic orbitals that are combined.

Since there are two valence orbitals and there is only one p orbital among the valence orbitals, it is true that only one p orbital is needed to form molecular orbitals in boron.

Answer:

dissolved in the solute

Explanation:

A solvent is the component that dissolves the solute and is present in larger amount. The type of solution is determined by the state of the solute and solvent. If you have NaCl, a solid, dissolved in water, a liquid, the type of solution is a solid/liquid solution.

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:

#6  8.67x10²⁴ atoms

#7  

1. Atom

2. Formula unit

3. Molecule

4. Ion

Explanation:

#6 First we calculate how many carbon moles are there in 7.00 moles of C₂F₂, keeping in mind that there are 2 C moles per C₂F₂ mol:

As for carbon dioxide, there are 0.400 C moles in 0.400 moles of CO₂.

We calculate the total number of C moles:

Finally we calculate the number of atoms in 14.4 C moles, using Avogadro's number:

#7

Answer:

10.10

Explanation:

Step 1: Write the basic dissociation reaction for pyridine

C₅H₅N(aq) + H₂O(l) ⇌ C₅H₅NH⁺(aq) + OH⁻(aq)      Kb = 1.9 × 10⁻⁹

Step 2: Calculate [OH⁻]

For a weak base, we will use the following expression.

[OH⁻] = √(Cb × Kb) = √(9.2 × 1.9 × 10⁻⁹) = 1.3 × 10⁻⁴ M

Step 3: Calculate pOH

We will use the definition of pOH.

pOH = -log [OH⁻] = -log 1.3 × 10⁻⁴ = 3.9

Step 4: Calculate pH

We will use the following expression.

pH = 14 - pOH = 14 - 3.9 = 10.10