Which of the following is a physical property of a substance? A. Hardness B. Flammability C. Reactivity D. Toxicity

Moles are the number of particles in a given weight. So unless you state the amount of water, aluminum, salt, and baking soda no one can not consider which contain the most moles.

Answer:

Explanation:

For any system in equilibrium, the molar concentration of all the species on the reactant side are related to those on the product side by a constant known as the equilibrium constant [tex]K_{eq}[/tex].

For a given reaction:

              aA + bB ⇄ cC

 [tex]K_{eq}[/tex] =   [tex]\frac{[C]^{c} }{[A]^{a} [B]^{b} }[/tex]

The reaction equation is given as:

     [tex]CO_{g}[/tex] + 2H₂[tex]_{g}[/tex] ⇆CH₃OH [tex]_{g}[/tex]

Note: All the species are in gaseous phase.

            [tex]K_{eq}[/tex] = [tex]\frac{[CH_{3}OH ]}{[CO] [H_{2}] }[/tex]

Answer: [tex]K_c=\frac{[CH_3OH]{[CO][H_2]^2}[/tex]

Explanation:

Equilibrium constant is the ratio of the concentration of products to the concentration of reactants each term raised to its stochiometric coefficients. It is expressed as [tex]K_{eq}[/tex]

[tex]CO(g)+2H_2(g)\rightarrow CH_3OH(g)[/tex]

The equilibrium constant in terms of concentration is written as :

[tex]K_eq=\frac{[CH_3OH]{[CO][H_2]^2}[/tex]

Thus the correct answer choice is B.

Answer:

The correct answer is Cirrocumulus.

Explanation:

Cirrocumulus : Clouds forming broken layer of small fleecy clouds at higher altitudes.

Cumulonimbus  : Clouds forming a towering mass with flat base with flat base at lower altitude

Cumulus  : Cloud forming rounded masses heaped or stacked on each other above a flat base , fairly at lower altitudes.

Stratus : Clouds forming continuous horizontal gray sheet, usually during rain or snow.

The given image corresponds to description given as Cirrocumulus.

Answer: A

Explanation:

Answer:

Explanation:

Specific heat capacity can be defined as the heat required to raise the temperature of a unit mass of a substance by 1kelvin.

The heat capacity on the other hand, expresses the heat required to raise the temperature of  asubstance by 1kelvin.

When we use specific heat capacity, we are particular about the amount of heat that would be needed to actually cause a temperature change in a unit of a substance. This suggests that even if we don't have a complete substance, we can be sure that by knowing the mass of a unit of a body one can easily estimate how much heat is required to raise its temperature. The specific heat is fundamental in calculating the heat capacity of a body. Without the value of the specific heat, we cannot evalutate the heat capacity of a body.

Answer:

0.0057034 or 5.7034 * 10^-3

Answer:

An insulated container that measures temperature change is a calorimeter. It is used to calculate change in enthalpy (which is ΔH.)

Explanation:

Enthalpy characterize a system from the energy point of view and it depends on the changes in the temperature of the system, the pressure (which is held constant) and the volume of the system (you know this because is an isolated system. Using a calorimeter is a key step in calculating the enthalpy, let's say for a chemical reaction.

Answer:

2SO2 + 02 ====>2SO3

Explanation:

SO2 + O2 ===> SO3

The only thing you can do is balance the oxygens that are on the sulfurs. When you do that the oxygen (O2) can make the difference.

SO2 + O2 ===> 2SO3

Bring the oxygen on the right up to 6. When you do that, the sulfurs are out of balance. So balance the sulfurs.

2SO2 + 02 ====>2SO3

Your equation is now balanced. The trick is not to leave the number of oxygens on the right as an odd number. When you fix that problem, the equation will balance easily.

Species           S                 O

Left                  2                  2+4=6

Right                2                  2*3 =6

Balanced.

Answer:

[tex]\boxed{\text{Pressure and volume}}[/tex]

Explanation:

The measure of R is always the same, but the numbers may differ depending on the units you use.

For example, in SI units, R = 8.314 Pa·m³K⁻¹mol

If your measurement uses different units, you must either convert your units to SI or use a value of R consistent with your units.

If you use bars and litres,                       R = 0.083 14   bar·L·K⁻¹mol⁻¹.

If you use kilopascals and litres,            R = 8.314        kPa·L·K⁻¹mol

If you use atmospheres and litres,        R = 0.082 06 L·atm·K⁻¹mol⁻¹.

If you use Torr and cubic centimetres, R = 62 368     Torr·cm³ K⁻¹mol⁻¹.

The only units that don't change are "K⁻¹mol⁻¹".

[tex]\text{The quantities that affect the value of R are }\boxed{\textbf{pressure and volume}}[/tex]

Answer:

This one is easy. It's the Avogadros' Hypothesis or Avogadros' Law, where the equal volumes of gases in SAME conditions have an equal amount of molecules!

Answer:

Avagadro’s law states at constant temperature and pressure, volume is directly proportional to the number of molecules of the gas.

For example  

At STP that is standard temperature and pressure at which T = 273K and P = 1 atm

Volume occupied by 1 mole ([tex]6.022\times 10^{23}[/tex] gas molecules) of any gas is equal to 22.4L

That is

1 mole = 22.4L

2 mole = 44.8 L

3 mole = 67.2 L

So 1 mole of [tex]CO_2[/tex] gas =22.4L ([tex]6.022\times 10^{23}[/tex] gas molecules)

1 mole of [tex]H_2[/tex] gas =22.4L ([tex]6.022\times 10^{23}[/tex] gas molecules)

1 mole of [tex]Cl_2[/tex] gas =22.4L ([tex]6.022\times 10^{23}[/tex] gas molecules)

Answer:

A. Deposition Occurs

Explanation:

When a gas becomes ionized, deposition occurs.

Answer: Option (D) is the correct answer.

Explanation:

A plasma is defined as the state of matter in which gas exists in hot ionized formed that has similar number of positively charged ions and negatively charged electrons.

Whereas deposition is the change from gaseous to liquid or solid state in which particles come closer to each other.

Sublimation means direct conversion of solid into gaseous phase without undergoing liquid phase.

Thus, we can conclude that when a gas becomes ionized then a plasma is formed.

Answer:

3Ag⁺ + 3NO₃⁻ + 3Na⁺ + PO₄³⁻ → Ag₃PO₄(s) + 3Na⁺ + 3NO₃⁻

Explanation:

An ionic equation is a chemical equation where the electrolytes in aqueous solution are expressed as dissociated ions.

For the reaction:

3AgNO₃(aq) + Na₃PO₄(aq) → Ag₃PO₄(s) + 3 NaNO₃(aq)

AgNO₃(aq), Na₃PO₄(aq) and NaNO₃(aq) are dissociated in water thus:

AgNO₃(aq) → Ag⁺ + NO₃⁻

Na₃PO₄(aq) → 3Na⁺ + PO₄³⁻

NaNO₃(aq) → Na⁺ + NO₃⁻

The ionic equation is:

3Ag⁺ + 3NO₃⁻ + 3Na⁺ + PO₄³⁻ → Ag₃PO₄(s) + 3Na⁺ + 3NO₃⁻

I hope it helps!

Answer:

9.02×10⁻¹¹ mol NH₃

Explanation:

Convert nanograms to grams:

1.56 ng NH₃ × (1 g / 10⁹ ng) = 1.56×10⁻⁹ g NH₃

Convert grams to moles:

1.56×10⁻⁹ g NH₃ × (1 mol NH₃ / 17.3 g NH₃) = 9.02×10⁻¹¹ mol NH₃

The answer is 9.02×10⁻¹¹ mol NH₃

Convert nanograms to grams:

1.56 ng NH₃ × (1 g / 10⁹ ng) = 1.56×10⁻⁹ g NH₃

Convert grams to moles:

1.56×10⁻⁹ g NH₃ × (1 mol NH₃ / 17.3 g NH₃) = 9.02×10⁻¹¹ mol NH₃

A mass of a substance in grams is numerically equal to its molecular weight. Example: A gram-mole of salt (NaCl) is 58.44 grams.

Learn more about molecular weight here: https://brainly.com/question/1603500

#SPJ2

Answer:

Approximately 0.074 grams.

Explanation:

How does the electroplating works for copper? Copper exists as copper(II) ions [tex]\mathrm{Cu}^{2+}[/tex] in the copper(II) nitrate [tex]\rm Cu{(NO_3)}_2[/tex] solution. It takes two moles of electrons to reduce one mole of copper(II) ions [tex]\mathrm{Cu}^{2+}[/tex] to metallic copper [tex]\rm Cu[/tex].

[tex]\rm Cu^{2+}\;(aq) + 2\;e^{-} \to Cu\;(s)[/tex]. (Reduction half of the ionic equation.)

Start by finding the charge on the electrons that have been supplied to this electrochemical cell. After that,

For a constant direct current [tex]I[/tex], the charge [tex]Q[/tex] that has been delivered in time [tex]t[/tex] is equal to

[tex]Q = I \cdot t[/tex].

In case

[tex]Q[/tex] will be in Coulombs [tex]\mathrm{C}[/tex] (which is the same as [tex]\mathrm{A\cdot s}[/tex].)

For this electrochemical cell,

[tex]Q = I\cdot t = \rm 0.75\;A \times 300\;s = 225\;C[/tex].

The Faraday's Constant gives the size of charge (in Coulombs) on one mole of electrons.

[tex]F \approx \rm 96485.33212\;C\cdot mol^{-1}[/tex].

[tex]\displaystyle n(\mathrm{e^{-}}) = \frac{Q}{F} = \rm \frac{225\;C}{96485.33212\;C\cdot mol^{-1}}\approx 0.00233196\;mol[/tex].

Assume that copper(II) ions [tex]\mathrm{Cu}^{2+}[/tex] are in excess. Refer to the reduction half-equation, it takes two moles of electrons to deposit one mole of metallic copper.

[tex]\displaystyle \frac{n(\mathrm{Cu})}{n(\mathrm{e^{-}})} = \frac{1}{2}[/tex].

[tex]n(\mathrm{e^{-}})=\rm 0.00233196\;mol[/tex]. As a result,

[tex]\displaystyle n(\mathrm{Cu}) = n(\mathrm{e^{-}})\cdot \frac{n(\mathrm{Cu})}{n(\mathrm{e^{-}})} = \rm 0.00233196\;mol\times \frac{1}{2} = 0.00116598\; mol[/tex].

The Relative atomic mass of copper is [tex]63.546[/tex].

[tex]\begin{aligned}m(\mathrm{Cu})& = n(\mathrm{Cu}) \cdot M(\mathrm{Cu})\\& = \rm 0.00116598\; mol\times 63.546\; g\cdot mol^{-1}\\&\rm \approx 0.074\;g\end{aligned}[/tex].

Final answer:

The mass of copper that can be plated from a 1.0 M Cu(NO3)2 solution using 0.75 A for 5 minutes is calculated by converting the charge passed to moles of electrons, determining the moles of copper, and then converting it to mass, resulting in approximately 0.0740 grams.

Explanation:

To calculate the mass of copper that can be plated out of a 1.0 M Cu(NO3)2 solution using a current of 0.75 A for 5.0 minutes, we apply Faraday's laws of electrolysis and use the molar mass of copper.

Firstly, calculate the total charge passed through the solution using the formula Q = It, where Q is the charge in Coulombs, I is the current in Amperes, and t is the time in seconds. For 0.75 A over 5.0 minutes (or 300 seconds), we obtain Q = (0.75 A) × (300 s) = 225 Coulombs.

Next, convert the charge to moles of electrons using the charge of one mole of electrons, known as Faraday's constant (approximately 96485 C/mol). Thus, moles of electrons = 225 C / 96485 C/mol ≈ 0.00233 mol.

Since the copper plating involves Cu2+ ions gaining two electrons to become copper atoms (Cu2+ + 2e− → Cu), the moles of copper plated will be half the moles of electrons. So, 0.00233 mol / 2 = 0.001165 mol of copper.

Finally, calculate the mass of copper by multiplying the moles of copper by its molar mass (63.55 g/mol for Cu). Thus, mass of copper = 0.001165 mol × 63.55 g/mol ≈ 0.0740 g.

Therefore, the mass of copper that can be plated out using these conditions is approximately 0.0740 grams.

Answer:

Decrease the volume or increase the number of moles by a factor of 37.

Explanation:

If the contents are a gas,

pV = nRT

If T is constant

[tex]p \propto \dfrac{n}{V}[/tex]

There are two ways to increase the pressure inside the container.

1. Decrease the volume

If you decrease the volume by a factor of 37, the pressure will increase by the same factor.

2 Increase the number of moles

If you add 36 times the number of moles, you will have 37n moles. Increasing the amount of gas by a factor of 37 increases the pressure by the same factor.

To increase the pressure inside a container by a factor of 37 while keeping the temperature constant, the volume of the gas must be reduced to 1/37th of its original volume, as per Boyle's Law, which states that pressure and volume are inversely proportional.

Assuming the temperature is held constant, to increase the pressure inside a container by a factor of 37, you must reduce the volume of the gas. This is based on Boyle's Law, which states that, for a given mass of gas at constant temperature, the pressure of the gas is inversely proportional to its volume. This means if you want to increase the pressure inside the container, you have to decrease the volume of the container correspondingly.

For instance, if the original pressure of the gas is P, and the volume is V, to increase the pressure by a factor of 37 (making it 37P), you would need to reduce the original volume (V) to V/37. This is because P1*V1 = P2*V2, where P1 and V1 are the initial conditions and P2 and V2 are the final conditions, assuming no change in the amount or temperature of the gas.

Magnesium oxide is an ionic compound ( because it consists of a metal and a non-metal)

In ionic compounds, electrons from the outer shell exchange between the atoms so that they each get a full outer shell. Once these electrons are exchange, the atoms will become ions. One ion will have a positive charge, and the other ion will have a negative charge. The positive and negative ions then bond strongly together in a lattice structure, due to the electrostatic forces of attraction.

These electrostatic forces of attraction are very strong and require a lot of energy to break, as such the compound will have a high melting point.

__________________________________________

Now lets look at the ionic bonding between magnesium and oxygen:

In the outer shell of Magnesium, there are 2 electrons.

In the outer shell Oxygen, there are 6 electrons.

Magnesium gives it's two electrons to Oxygen, so that the Oxygen now has a full outer shell of 8 electrons. However, since Oxygen gained two electrons, it will form a negatively charged ion with a charge of -2.

Since Magnesium lost the two electrons, it's second shell (which has 8 eletrons) now becomes the outer shell. So Magnesium also now has a full outer shell. But since it has lost two electrons, it becomes a positively charged ion with a charge of + 2.

The positive Magnesium ion and negative Oxygen ion and now strongly attracted to each other, and form a strong ionic compound (magnesium oxide) with a lattice structure.

The electrostatic forces of attraction between the positive Magnesium and negative Oxygen are so strong that a lot of heat and energy are needed to break them.

Therefore magnesium oxide has a high melting point.

Answer:

Na₂CO₃•H₂O

Explanation:

After it is heated, the remaining mass is the mass of sodium carbonate.

30.2 g Na₂CO₃

Mass is conserved, so the difference is the mass of the water:

35.4 g − 30.2 g = 5.2 g H₂O

Convert masses to moles:

30.2 g Na₂CO₃ × (1 mol Na₂CO₃ / 106 g Na₂CO₃) = 0.285 mol Na₂CO₃

5.2 g H₂O × (1 mol H₂O / 18.0 g H₂O) = 0.289 mol H₂O

Normalize by dividing by the smallest:

0.285 / 0.285 = 1.00 mol Na₂CO₃

0.289 / 0.285 = 1.01 mol H₂O

The ratio is approximately 1:1.  So the formula of the hydrate is Na₂CO₃•H₂O.

Na₂CO₃•H₂O

Given:

Question:

What is the formula for the hydrate?

Problem-solving:

We will solve problems related to The Law of Definite Proportion (Proust's Law).

"The ratio of the masses of elements in each compound is always constant. Put differently, a given compound invariably contains a similar proportion of elements by mass."

The heating reaction of the hydrate of sodium carbonate is as follows:

[tex]\boxed{ \ Na_2CO_3.nH_2O \xrightarrow{\text{heat}} Na_2CO_3 + nH_2O \ }[/tex]

Condition:

[tex]\boxed{ \ Na_2CO_3.nH_2O \xrightarrow{\text{heat}} Na_2CO_3 + nH_2O \ }[/tex]

         35.4 g                 30.2 g       5.2 g

We want to determine the amount of water (with the symbol n) so that the formula for the hydrate can be known.

Recall that [tex]\boxed{ \ Moles = \frac{Mass \ (g)}{Mr} \ }[/tex]

Let us prepare the number of moles of Na₂CO₃ and H₂O respectively.

Finally, we use the mole ratio to write the formula. Find the water-to-anhydrate mole ratio.

[tex]\boxed{ \ Na_2CO_3 \ : \ H_2O = 1 \ : \ n  \ }[/tex]

[tex]\boxed{ \ H_2O \ : \ Na_2CO_3 = n \ : \ 1  \ }[/tex]

[tex]\boxed{ \ n \ : \ 1 = 0.289 \ : \ 0.285 \ }[/tex]

[tex]\boxed{ \ n = \frac{0.289}{0.285} \times 1 \ }[/tex]

Thus, the value of n after rounding is [tex]\boxed{ \ n = 1 \ }[/tex]

Substitute n = 1 into Na₂CO₃•nH₂O.

Therefore, the formula for the hydrate is [tex]\boxed{\boxed{ \ Na_2CO_3.H_2O \ }} [/tex]

Keywords: 35.40 gram, hydrate of sodium carbonate, Na₂CO₃•nH₂O, heating, a constant mass, its final weight, 30.2 g, what is the formula for the hydrate? the law of definite proportion, Proust's law, anhydrate, the mole ratio

Answer:

A pie chart

Explanation:

A pie chart would be the ideal type of chart to create this visual aid. A pie chart is simpler visually and easily understood. It can show data as portions or percentages of a whole. Since what they want is to present the different gases found in Earth's atmosphere, they can show what percentage of the different gases make up the atmosphere.

It is simpler because the size of each portion or "slice" of the pie chart itself can reveal a lot about the data without even reading the numbers.

Answer:

Pie chart

Explanation:

13 An Ionic Bond

these are the characteristics of an ionic bond compounds like NaCl have these characteristics

14 substances could be compounds or elements hence not all substances are compounds

15 It is not water. The chemical composition of water is H2O not H202

(H202 is hydrogen peroxide and is toxic)

Na2C03 is formed through the reaction of

NaOH and H2CO3 namely sodium hydroxide and carbonic acid

NaOH -> strong base

H2CO3-> weak acid

Answer:

A. a weak acid and a strong base

Explanation:

An acid-base reaction is a chemical reaction between an acid and a base to form salt and water. The reaction is also known as a neutralization reaction.

An acid is a compound that when in aqueous solution it dissociate to form an hydrogen ion(H+).

A base is a compound that when in aqueous solution it produces an hydroxide ion(OH-) .

A strong acid is an acid that completely dissociate in an aqueous solution.

A strong base is a base that completely dissociate in an aqueous solution.

The reaction that produce a salt like sodium carbonate is a chemical reaction between a weak acid and a strong base. The chemical reaction can be represented as follows

H2CO3 + 2NaOH → Na2CO3 + 2H2O

H2CO3 is a weak acid as it partially dissociate in aqueous solution.

NaOH is a strong base as it completely dissociate in aqueous solution.

Answer:

2RbNO₃ + BeF₂ → Be(NO₃)₂ + 2RbF, because Be keeps a 2+ charge throughout the reaction

Explanation:

2RbNO₃ + BeF₂ → Be(NO₃)₂ + 2RbF, because Be keeps a 2+ charge throughout the reaction

Rb is a +1 cation, NO3 is a -1 anion, Be is a +2 cation and F is a -1 anion.

In writing an ionic compound the charge of the cation becomes the subscript of the anion and the charge of the anion becomes the subscript of the cation.  

So the ionic compound formed between Be2+ and F- is BeF2. The ionic compound formed between Be2+ and NO3- is Be(NO₃)₂.  

As there are two NO₃ on the product side it is balanced by writing a 2 coefficient before RbNO₃ on the reactant side.  

And as there are two F on the reactant side it is balanced by writing a 2 coefficient before RbF on the product side.  

Answer:

2RbNO3 + BeF2 → Be(NO3)2 + 2RbF, because Be keeps a 2+ charge throughout the reaction

Answer:

[tex]\boxed{\text{ 93 \%}}[/tex]

Explanation:

[tex]\text{\% yield} = \dfrac{\text{actual yield}}{\text {theoretical yield}} \times\text{100 \%}[/tex]

Data:

[tex]\begin{array}{rcr}\text{Actual yield} & = & \text{74.3 T}\\\text{Theoretical yield} & = & \text{80 T}\\\end{array}[/tex]

Calculation:

[tex]\text{\% yield} = \dfrac{\text{74.3 T}}{\text {80 T}} \times\text{100 \%} = \textbf{93 \%}}\\\\\text{The percent yield was } \boxed{\textbf{93 \%}}[/tex]

Answer:

Reactivity

Explanation:

The scenario shows that baking soda is reactive enough to produce bubbles with vinegar but not enough to do so in pure water.

Flammability, color change, and boiling point are all wrong.  The scenario says nothing about these properties.

Answer:

Reactivity (Znk Elite Answerer is right)

Explanation:

I just took a test and I got it right. Even if the question says select all that apply there is only 1 answer and it is reactivity

Answer:

Protons and neutrons form the nucleus of the atom with electrons orbiting it.- C.

The correct answer is C. Protons and neutrons form the nucleus of the atom with electrons orbiting it

Explanation:

Bohr model was proposed by Niels Bohr in 1913 to explain the structure of atoms, in this Bohr stated electrons (particles negatively charge) orbit the nucleus that contains both neutrons (neutral particles) and protons (positively charged particles). Additionally, according to this model electrons were placed in different levels of energy and orbit the nucleus constantly, resembling planets in the Solar System, although the Bohr model was the first one that integrated principles related to energy levels and changes in energy in electrons. Thus, Bohr proposed "Protons and neutrons form the nucleus of the atom with electrons orbiting it".

Answer:

4.81×10⁻⁴ g K

Explanation:

Convert atoms to moles:

7.40×10¹⁸ atoms K × (1 mol K / 6.02×10²³ atoms) = 1.23×10⁻⁵ mol K

Convert moles to mass:

1.23×10⁻⁵ mol K × (39.1 g K / mol K) = 4.81×10⁻⁴ g K