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a)
b)
c)
d)

Answer:

All of the above

Explanation:

Molecules make up matter so they are considered matter as well.

Hope it helps c:

Answer:

Kc = [Zn²⁺] / [Cd²⁺]

Explanation:

Let's consider the spontaneous redox reaction between Cd²⁺ and Zn.

Cd²⁺(aq) + Zn(s) ⇄ Cd(s) + Zn²⁺(aq)

The equilibrium constant, Kc, is the ratio of the equilibrium concentrations of products over the equilibrium concentrations of reactants each raised to the power of their stoichiometric coefficients. It only includes gases and aqueous species.

Kc = [Zn²⁺] / [Cd²⁺]

Answer:

19.25g of C4H10

Explanation:

2C4H10

2×12×4+2×1×10

=116g

8CO2

=8×12+8×16×2

=352 g

116g of C4H10 produces 352 g of CO2

So, x g of C4H10 produces 58.4g of CO2

(cross multiply)

352 x=116×58.4

x=116×58.4÷352

x=19.25g of C4H10

Answer:

19.25g of C4H10

2C4H10

2×12×4+2×1×10

=116g

8CO2

=8×12+8×16×2

=352 g

116g of C4H10 produces 352 g of CO2

So, t g of C4H10 produces 58.4g of CO2

(cross multiply)

352 t=116×58.4

t=116×58.4÷352

t=19.25g of C4H10

Explanation:

Answer:

WAS THE VOOK NAME =THE BOY WHO HARNESSED THE WIND?

1.How did environmental factors affect food production? They could not grow any crops

2. What does William’s windmill allow him to have that he didn’t before? How does life change for him and his family? His windmill allowed him and his family to be able to regrow crops and have unlimited water. Life changes because don’t have to worry about drought issues.

3.Why are trees important to farmers in William’s village? The trees are important because they stop floods. Now whenever it rains the trees can soak up the water.4.Could you imagine living without electricity? What would your life be like? Describe William's life and compare it to American teenagers and even your own. I could not imagine living without electricity. If I lived without electricity, I think my life would be kind of hard at first but after a while I would have to get used to it. William had to depend on the sun for all his light a normal teenager can cut the lights on and off in

Answer:

See explanation

Explanation:

Number of moles = reacting mass/molar mass

Number of moles of CaCl2•2H2O = 1.50 g/147.02 = 0.0102 moles

From the equation;

Na2CO3 + CaCl2•2H2O -> CaCO3 + 2NaCl + 2H2O

We can see is 1:1

1 mole of Na2CO3 reacts with 1 mole of CaCl2•2H2O

x moles of Na2CO3 reacts with 0.0102 moles of CaCl2•2H2O

x = 1 × 0.0102 moles/1

x = 0.0102 moles of Na2CO3

Mass of Na2CO3 = 0.0102 moles of Na2CO3 × 106g/mol = 1.08 g of Na2CO3

Answer: CH3NH2

Explanation:

Solution :

The smallest integer value represents the smaller number of protons.

In this case, in the given values, the smallest numbers are 8 mm and 9 mm, so both contains 1H each. Then next highest  value is 17 mm, which contains 1H more. Thus 17 mm contains 2H each. Then the next highest is 25 mm and 26 mm which contains 3M each and so on.

Thus the tables is :

Integral     Protons

52 mm           [tex]6[/tex]

17 mm            [tex]2[/tex]

17 mm            2

26 mm           3

17 mm            2

25 mm           3

26 mm           3

9 mm              1

9 mm              1

35 mm            4    

8 mm              1

Answer:

are in the same orbital

Explanation:

Answer:

are in the same orbit

Explanation:

Answer:

CH3OH < FCH2OH < F2CHOH < F3COH

Explanation:

Let us recall that, for a carboxylic acid, the dissociation of the acid yields;

RCOOH ⇄RCOO^- + H^+

The ease of dissociation and release of the hydrogen ion depends on the nature of the group designated R.

When R is is a highly electronegative element, the -I inductive effect causes the hydrogen to become less tightly held by the C-Cl bond.

As the number of electron withdrawing substituents increaseses, the acid ionizes much more and becomes stronger.CH3OH < FCH2OH < F2CHOH < F3COH

Hence, the order of decreasing acid strength is;

The answer below is correct but to give you the process, here it is:

Molar mass of iron, Fe = 55.85 g/mol

3.30g/(55.85 g/mol) = 0.0591 mol

First Reaction is a Decomposition reaction as a single reactant hets decompoesed to form two products.Second reaction is a Synthesis reaction as two Reactant reacts together to form one product.

Decomposition reactions are processes in which chemical species break up into simpler parts.

Usually, decomposition reactions require energy input.

Hence, First Reaction is a Decomposition reaction as a single reactant hets decompoesed to form two products.Second reaction is a Synthesis reaction as two Reactant reacts together to form one product.

Learn more about Reaction here ;

https://brainly.com/question/27948961

#SPJ2

Answer:

D. 3.04 × 10^-19 J

Explanation:

c = lambda * nunu = c/lambda

E = h* nu

E = h * c/lambda = 6.626x10^-34 J-sec * 3x10^8 m/sec / 6.54x10^-7 m

E = 3.04x10^-19 J

Answer:

Covalent bonding occurs when pairs of electrons are shared by atoms.

Explanation:

Atoms will covalently bond with other atoms in order to gain more stability, which is gained by forming a full electron shell. By sharing their outer most (valence) electrons, atoms can fill up their outer electron shell and gain stability.

Answer:

3-

Explanation:

Sodium aurothiosulfate is a salt with the formula Na₃Au(S₂O₃)₂. The cation of the salt is sodium ion, and the anion is aurothiosulfate ion. We can determine the charge of the aurothiosulfate ion, considering that the sum of the positive and negative charges must be equal to the charge of the compound, which is zero.

3 × Na⁺ + 1 × Au(S₂O₃)₂ⁿ⁻ = 0

3 × +1 + 1 × Au(S₂O₃)₂ⁿ⁻ = 0

Au(S₂O₃)₂ⁿ⁻ = 3-

Answer:

The pH of the solution is 12.78.

Explanation:

The pOH (or potential OH) is a measure of the basicity or alkalinity of a solution. The pOH is defined as the negative logarithm of the activity of the hydroxide ions. That is, the concentration of OH- ions:

pOH= - log [OH-]

On the other side, Molarity or Molar Concentration is the number of moles of solute that are dissolved in a certain volume. Molarity is calculated as:

[tex]Molarity= \frac{number of moles}{volume}[/tex]

Molarity is expressed in units: [tex]\frac{moles}{liter}[/tex]

In this case, the solution is prepared by mixing 100 ml (equal to 0.1 L, where 1000 mL = 1 L) of Ca(OH)₂ 0.020 M with 50 ml (equal to 0.05 L) of 0.100 M NaOH. Then, Ca(OH)₂ and NaOH are strong bases, so they dissociate completely. In the case of the first hydroxide, for each mole of Ca(OH)₂,

form two moles of OH-. In the case of sodium hydroxide, for each mole of hydroxide, one mole of OH- is formed. So, taking into account the definition of molarity, the number of moles of OH- that each hydroxide contributes to the solution is calculated as:

From Ca(OH)₂: 0.1 L* 0.02 M*2 = 0.004 moles

From NaOH: 0.05 L* 0.1 M= 0.005 moles

So, the amount of total moles of OH- is the sum that each hydroxide contributes to the solution: 0.004 moles + 0.005 moles= 0.009 moles

On the other hand, volumes are additive. Then: 0.1 L +  0.05 L= 0.15 L

Replacing in the definition of molarity the number of moles and the volume:

[tex][OH-]=\frac{0.009 moles}{0.15 L}[/tex]

Solving:

[OH-]= 0.06 [tex]\frac{moles}{liter}[/tex]

Replacing in the definition of pOH:

pOH= - log 0.06

pOH= 1.22

The following relationship can be established between pH and pOH:

pH + pOH= 14

Being pOH= 1.22 and replacing:

pH + 1.22= 14

pH= 14 - 1.22

pH= 12.78

The pH of the solution is 12.78.

Answer:

[tex]{ \tt{1 \: mole = 6.02 \times {10}^{23} \: molecules }} \\ { \tt{6.0 \: moles = (6 \times 6.02 \times {10}^{23}) \: molecules }} \\ = { \bf{3.612 \times {10}^{24} \: molecules}}[/tex]

Answer:

An unsaturated solution.

Explanation:

Hello there!

In this case, according to the given information, it turns out possible for us to firstly realize we need to calculate the grams of vanillin in 0.070 moles by using its molar mass of 152.15 g/mol:

[tex]m=0.070mol*\frac{152.15 g}{1mol} =10.65g[/tex]

Thus, since the solubility is 10.65 g per 1 L of solution, we can notice 5.00 g will complete dissolve and produce an unsaturated solution.

Best regards!

Answer:

2.23M

Explanation:

Molarity of a solution is calculated thus

Molarity = number of moles (n) ÷ volume (V)

According to this question, 4.11g of Zn metal was used in order to reach a volume of EDTA solution of 28.26 mL.

28.26mL = 28.26/1000

= 0.02826L

Using mole = mass/molar mass to calculate no. of moles of Zn

Mole = 4.11/65.4

mole = 0.0628mol

Molarity = 0.0628 ÷ 0.02826

Molarity = 2.23M

The concentration of the EDTA solution used is 2.23M

Answer:

40.5 g of P₄O₁₀ are produced

Explanation:

We state the reaction:

P₄ + 5O₂ → P₄O₁₀

We do not have data from P₄ so we assume, it's the excess reactant.

We need to determine mass of oxygen and we only have volumne so we need to apply density.

Density = mass / volume, so Mass = density . volume

Denstiy of oxygen at STP is: 1.429 g/L

1.429 g/L . 16.2L = 23.15 g

We determine the moles: 23.15 g . 1mol / 33.472g = 0.692 moles

5 moles of O₂ can produce 1 mol of P₄O₁₀

Our 0.692 moles may produce (0.692 . 1)/ 5 = 0.138 moles

We determine the mass of product:

0.138 mol . 292.88 g/mol = 40.5 g

Answer:

A) greater than the Ksp

Explanation:

Given a solid ionic compound AB, it dissociates in water into its ions, as follows:

AB(s) → A⁺(aq) + B⁻(aq)

At equilibrium, the product of the concentrations of the ions is constant, and it is called Ksp:

AB(s) ⇄ A⁺(aq) + B⁻(aq)

Ksp = [A⁺][B⁻] ⇒ (concentrations at equilibrium)

Upon mixing the reagents for the formation of AB, the compound will precipitate if the initial ion product (Q) is greater than the Ksp. If Q is equal to Ksp, the ions are at equilibrium with the solid compound AB, and if is it less than the Ksp, the ions are soluble and no solid AB is formed yet.

Q = [A⁺][B⁻] ⇒ (initial concentrations)

Q = Ksp ⇒ saturated solution (at equilibrium)

Q< Ksp ⇒ unsaturated solution (ions are soluble)

Q> Ksp ⇒ precipitation of solid compound.

Therefore, the correct option is A) greater than the Ksp

Answer:

Explanation:

Molecular FormulaC4H7O2

Average mass87.098 Da

Monoisotopic mass87.045151 Da

Answer:

[tex]n_{O_2}^{leftover}=7.7mol[/tex]

Explanation:

Hello there!

In this case, according to the given information, it turns out firstly necessary for us to set up the corresponding chemical equation:

[tex]4Al+3O_2\rightarrow 2Al_2O_3[/tex]

In such a way, we calculate the moles of aluminum consumed by 13.0 moles of oxygen in the reaction, by applying the 4:3 mole ratio between them:

[tex]n_{Al}=13.0molO_2*\frac{4molAl}{3molO_2} =17.3molAl[/tex]

This means that Al is actually the limiting reactant and oxygen is in excess, for that reason we calculate the moles of oxygen consumed by 7.0 moles of aluminum:

[tex]n_{O_2}=7.0molAl*\frac{3molO_2}{4molAl} =5.3molO_2[/tex]

Thus, the leftover of oxygen is:

[tex]n_{O_2}^{leftover}=13.0mol-5.3mol\\\\n_{O_2}^{leftover}=7.7mol[/tex]

Whereas all the aluminum is assumed to be consumed.

Regards!

Answer:

No it is not an exception to this principle

Explanation:

Work was carried out by this compressor to reduce the entropy of ice. What this means is that the ice gave out heat which is as a result  of the work that the compressor was putting in. there are violations of this principle

the entropy principle has that the entropy of the universe is always going to be more than 0 (system + surrounding). in this question, the that of the system is negative while that of the surrounding is positive.  As the refrigerator was cooling the water, the air outside was getting heated.  Outside this refrigerator, the gain in entropy is more than the entropy that was lost in the water.

the entropy of the universe once again is more than 0.

Answer:

See explanation

Explanation:

Extraction has to do with the separation of the components of a mixture by dissolving the mixture in a set up involving two phases. One phase is the aqueous phase (beneath) while the other is the organic phase (on top). The solvents used for the two phases must not be miscible. Water commonly is used for the aqueous phase.

Ethanol is an important solvent in chemistry but the solvent is miscible with water in all proportions. As a result of this, ethanol is a poor solvent for carrying out extraction.

Answer:

c

letra c certeza confia

Answer:

See explanation

Explanation:

Aspirin is a very important pain killer. The production of aspirin involves a reaction between salicylic acid and excess acetic anhydride.

Usually, a small amount of a mineral acid is added as a catalyst.

Aspirin is actually acetyl salicylic acid. When this substance is formed, the substance is not really soluble in water. Addition of water leads to the precipitation of the aspirin product.

Hence, the addition of water is mostly to precipitate the pure aspirin product after reaction.

Answer:

925.66 J/K

Explanation:

Applying,

Q = CΔt............. Equation 1

Where Q = amount of heat, C = heat capacity of the calorimeter, Δt = rise in temperature.

make C the subject of the equation

C = Q/Δt.............. Equation 2

From the question,

Given: Q = 3.86 kJ = 3860 J, Δt = 4.17K

Substitute into equation 2

C = 3860/4.17

C = 925.66 J/K

Answer:

1.00 M

Explanation:

Sn^2+ reacts with KMNO4 as follows;

5Sn^2+(aq) + 2MnO4^-(aq) + 16H^+(aq) ----> 5Sn^4+(aq) + 2Mn^+(aq) + 8H2O(l)

The number of moles of MnO4^- reacted = 42.1/1000 L × 0.145 mol/L

= 0.0061 moles

If 5 moles of Sn^2+ reacts with 2 moles of MnO4^-

x moles of Sn^2+ reacts with 0.0061 moles of MnO4^-

x= 5 × 0.0061/2

x= 0.015 moles

Since the volume of the Sn^2+ solution is 15.00mL or 0.015 L

number of moles = concentration × volume

Concentration = number of moles/volume

Concentration= 0.015 moles/0.015 L

Concentration = 1 M

Answer:

[tex]particles=1.42x10^{23}[/tex]

Explanation:

Hello there!

In this case, according to the given information, it turns out possible for us solve this problem by using the ideal gas law:

[tex]PV=nRT[/tex]

Which can be modified to include the particles in terms of the Avogadro's number:

[tex]PV=\frac{particles}{N_A} RT[/tex]

Thus, if we solve for the particles, we will obtain the expression and the numerical result:

[tex]particles=\frac{PV*N_A}{RT}[/tex]

[tex]particles=\frac{1.0atm*6.0L*6.022x10^{23}}{0.08206\frac{atm*L}{mol*K}*310K} \\\\particles=1.42x10^{23}[/tex]

Regards!