When we test sucrose with seliwanoff's test what would the result be positive or negative ? Before and after hydrolysis of sucrose .

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All the options are solved and answer is written below

A reaction between two or more compounds to form products made after chemical change is called a chemical reaction.

It is given that

A chemical reaction was carried out by mixing 25 g of pure CaCO₃ and 0.75 mole of pure HCl

CaCl₂ , H₂O and CO₂  are the products obtained.

CaCO₃ + 2HCl → CaCl₂ + CO₂ + H₂O

Mole ratio CaCO₃ : HCl : CaCl₂ : H₂O = 1 : 2 : 1 : 1

Molar mass of CaCO₃  = 100 g/mol

Molar mass of HCl  = 36.5 g/mol

Molar mass of H₂O = 18 g/mol

Molar mass of CaCl₂= 110.98 g/mol

Moles of CaCO₃ = 25/100 = 0.25 moles

Moles of HCl present = 0.75 mole

For 0.25 moles of CaCO₃ 0.5 moles of HCl is required , as the moles of HCl is present in excess therefore

a. CaCO₃ is the limiting reactant

b. mass of CaCl₂ produced

Moles of CaCl₂  produced = 0.25 moles

1 mole means 110.98 gm

0.25 mole means 0.25* 110.98 = 27.74 gm

c. moles of water molecules formed

for 0.25 moles of CaCO₃ 0.25 moles of water will be formed

d.Volume of Co produced at STP

PV = nRT

P= 1 atm

V=?

R = 0.0821 atm L/K/mol

V = 0.25 * 0.0821 * 273 /1

V = 5.6 liter

e. The mass of NaOH required to absorb CO₂ produced in the reaction

Ratio of NaOH:CO₂ = 2 :1

0.5 moles will be required , i.e.

0.5 *40

20 grams of NaOH will be required.

To know more about Chemical Reaction

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Explanation:

The chemical formula of an ionic compound can be written by using the symbols of the respective cations and anions.

The overall charge on the molecule should be zero.

Hence, the total charge of cations=total charge of anions.

The symbols of the given molecules are shown below:

sodium chloride  ---- NaCl

magnesium chloride ---[tex]MgCl_2[/tex]

calcium oxide ---- CaO

lithium phosphide----[tex]Li_3P[/tex]

aluminum sulfide ----- [tex]Al_2S_3[/tex]

calcium nitride---- [tex]Ca_3N_2[/tex]

Answer:

- Two black balls: they represent a diatomic molecule composed by two atoms of the same element.

- One black ball and two black balls: they represent a compound formed by two different elements.

- One gray ball and two black balls: they represent a compound formed by two different elements.

- Two black-dotted balls: they represent a diatomic molecule composed by two atoms of the same element.

Explanation:

Hey there!

In this case, according to the given information, we can firstly bear to mind the fact that each ball color represents a different element, for that reason we can tell the following:

- Two black balls: they represent a diatomic molecule composed by two atoms of the same element.

- One black ball and two black balls: they represent a compound formed by two different elements.

- One gray ball and two black balls: they represent a compound formed by two different elements.

- Two black-dotted balls: they represent a diatomic molecule composed by two atoms of the same element.

Regards!

Answer:

Percent yield  = 72.07 %

Explanation:

Our reaction is:

C₄H₁₀O + NaBr + H₂SO₄ → C₄H₉Br + NaHSO₄ + H₂O

It is correctly balanced.

Let's determine which is the limiting reagent:

45 g . 1 mol / 74 g = 0.608 moles of C₄H₁₀O

67.1 g . 1 mol / 102.9 g = 0.652 moles of NaBr

97 g . 1 mol / 98 g = 0.990 moles of sulfuric acid

Ratio is always 1:1, so for 1 mol of NaBr and 1 mol of sulfuric acid we need 1 mol of C₄H₁₀O. We have 0.652 moles of NaBr, we need the same amount of C₄H₁₀O and we have 0.990 moles of acid, we need the same amount of C₄H₁₀O; we only have 0.608 moles, that's why C₄H₁₀O is the limiting reactant, there's no enough C₄H₁₀O.

Ratio is also 1:1, between reactant and product.

1 mol of C₄H₁₀O produces 1 mol of C₄H₉Br

Then, 0.608 moles will produce 0.608 moles of C₄H₉Br

We convert moles to mass: 0.608 mol . 136.9 g/mol = 83.25 g

That's the 100 % yield reaction

Percent yield  = (Yield produced / Theoretical yield) . 100

Percent yield = (60 g / 83.25 g) . 100 = 72.07 %

Answer:

1) 0.00498 mol Cu.

2) 0.00000374 mol CO₂

Explanation:

Question 1)

We want to convert 3.00 * 10²¹ copper atoms into moles. Note that 3.00 is three significant figures.

Recall that by definition, one mole of a substance has exactly 6.022 * 10²³ amount of that substance. In other words, we have the ratio:

[tex]\displaystyle \frac{1\text{ mol}}{6.022\times 10^{23} \text{ Cu}}[/tex]

We are given 3.00 * 10²¹ Cu. To cancel out the Cu, we can multiply it by our above ratio with Cu in the denominator. Hence:

[tex]\displaystyle 3.00 \times 10^{21} \text{ Cu} \cdot \frac{1\text{ mol Cu}}{6.022\times 10^{23} \text{ Cu}}[/tex]

Cancel like terms:

[tex]=\displaystyle 3\times 10^{21} \cdot \frac{1\text{ mol Cu}}{6.022\times 10^{23} }[/tex]

Simplify:

[tex]\displaystyle = \frac{3\text{ mol Cu}}{6.022 \times 10^{2}}[/tex]

Use a calculator:

[tex]= 0.004981... \text{ mol Cu}[/tex]

Since the resulting answer must have three significant figures:

[tex]= 0.00498\text{ mol Cu}[/tex]

So, 3.00 * 10²¹ copper atoms is equivalent to approximately 0.00498 moles of copper.

Question 2)

We want to convert 2.25 * 10¹⁸ molecules of carbon dioxide into moles. Note that 2.25 is three significant digits.

By definition, there will be 6.022 * 10²³ carbon dioxide molecules in one mole of carbon dioxide. Hence:

[tex]\displaystyle \frac{6.022 \times 10^{23} \text{ CO$_2$}}{1\text{ mol CO$_2$}}[/tex]

To cancel the carbon dioxide from 2.25 * 10¹⁸, we can multiply it by the above ratio with the carbon dioxide in the denominator. Hence:

[tex]\displaystyle 2.25\times 10^{18} \text{ CO$_2$} \cdot \frac{1\text{ mol CO$_2$}}{6.022\times 10^{23} \text{ CO$_2$}}[/tex]

Cancel like terms:

[tex]\displaystyle= 2.25\times 10^{18} \cdot \frac{1\text{ mol CO$_2$}}{6.022\times 10^{23}}[/tex]

Simplify:

[tex]\displaystyle = \frac{2.25 \text{ mol CO$_2$}}{6.022\times 10^5}}[/tex]

Use a calculator:

[tex]=0.000003736...\text{ mol CO$_2$}[/tex]

Since the resulting answer must have three significant figures:

[tex]= 0.00000374\text{ mol CO$_2$}[/tex]

So, 2.25 * 10¹⁸ molecules of carbon dioxide is equivalent to approximately 0.00000374 moles of carbon dioxide.

Answer:

Explanation:

by definition, 1 mole contains 6.02 x 10^23 of atoms (for elements) or molecules (for compounds)

3.00 x 10^21 atoms of copper / 6.02 x 10^23 of atoms

= 0.004983 moles of copper

= 4.98 x 10^(-3) moles of copper

2.25 x 10^18 molecules of carbon dioxide / 6.02 x 10^23 of molecules

= 0.000003737 moles of carbon dioxide

= 3.74 x 10^(-6) moles of carbon dioxide

Answer:

The reaction between hydrogen and fluorine.

Explanation:

The balanced chemical equation of the reaction is:

[tex]H_2(g)+F_2(g)->2HF(g)[/tex]

From the balanced chemical equation, it is clear that:

1 mole of [tex]H_2[/tex] gas reacts with one mole of [tex]F_2(g)[/tex] and forms 2 moles of HF(g).

Explanation:

Conjugated diene is the one that contains alternate double bonds in its structure. That means both the double bonds are separated by a single bond.

Cumulated diene is the one that contains two double bonds on a single atom. This means it has two double bonds continuously.

Isolated double-bonded compound has a single bond isolated by two to three single bonds.

Compound A: Two alkenes are joined by a sigma bond.

For example:

[tex]-CH_2=CH-CH=CH2-[/tex]

It is a conjugated diene.

Compound B: Two alkenes are joined by a C H 2 group.

It is a cumulative diene.

Compound C: Two alkenes are joined by C H 2 C H 2.

Then it is an isolated alkene.

Compound D:  A cyclohexene has a double bond between carbons 1 and 2. Carbon 3 is an sp 2 carbon that is bonded to another s p 2 carbon with an alkyl substituent.

Hence, compound D is a conjugated diene.

El hidrógeno es el elemento químico de número atómico 1, representado por el símbolo H. Con una masa atómica de 1.00784 u  ​ es el más ligero de la tabla periódica de los elementos. Por lo general, se presenta en su forma molecular, formando el gas diatómico H₂ en condiciones normales.

Answer:

[tex][O_2]_{eq}=0.030M[/tex]

Explanation:

Hello there!

In this case, according to the given information, it turns out possible for us to solve this problem by firstly writing out the mathematical expression for the concentration of oxygen at equilibrium, given the initial one and the change due to the reaction extent:

[tex][O_2]_{eq}=0.050M-x[/tex]

Whereas [tex]x[/tex] can be found considering the equilibrium of SO3:

[tex][SO_3]_{eq}=2x=0.040M[/tex]

Which means:

[tex]x=\frac{0.040M}{2} =0.020M[/tex]

Thus, the equilibrium concentration of oxygen gas turns out:

[tex][O_2]_{eq}=0.050M-0.020M=0.030M[/tex]

Regards!

Answer:

See explanation

Explanation:

a) The balanced reaction equation is;

Na2CO3(aq) + Pb(OH)2(aq) -----> 2 NaOH + PbCO3

b) When we include states of matter;

Na2CO3(aq) + Pb(OH)2(aq) -----> 2 NaOH(aq) + PbCO3 (s)

c) Complete ionic equation;

2Na^+(aq) + CO3^2-(aq) + Pb^2+(aq) + 2OH^-(aq) ----> 2Na^+(aq) + 2OH^-(aq) + PbCO3(s)

Net Ionic equation;

Pb^2+(aq) + CO3^2-(aq) ----> PbCO3(s)

Answer:

The molarity is "0.050 M".

Explanation:

The given values are:

M1 = 0.100 M

M2 = ?

V1 = 25.0 mL

V2 = 50.0 mL

As we know,

⇒ [tex]M1\times V1=M2\times V2[/tex]

Or,

⇒ [tex]M2=\frac{M1\times V1}{V2}[/tex]

By putting the values, we get

          [tex]=\frac{0.100\times 25}{50}[/tex]

          [tex]=\frac{2.5}{50}[/tex]

          [tex]=0.05 \ M[/tex]

Answer:

C

Explanation:

An endothermic reaction has a positive enthalpy change (∆H> 0).

An endothermic reaction is where the energy of the products is higher than that of the reactants.

∆H= energy of products -energy of reactants

Thus, ∆H is positive since the value of the energy of products is greater than that of the reactants.

Exothermic reactions have a negative ∆H.

In an endothermic reaction, heat is absorbed and thus if we were to include heat in teh chemical equation, it would be part of the reactants not products.

∆H does not indicate the amount of activation energy (Ea). All reactions have activation energy (exothermic and endothermic reactions). Activation energy is the minimum amount of energy required for the reaction to proceed.

Answer:

[tex]\boxed {\boxed {\sf C. \ The \ reaction \ is \ endothermic}}[/tex]

Explanation:

There are two main types of reactions classified according to heat: exothermic and endothermic.

The ΔH is the change in enthalpy. It is the difference between the heat of the products and the reactants (ΔH = heat of products - heat of reactants). It helps us describe a system's change in heat and classify reactions as exothermic or endothermic.

In this problem, the change in enthalpy is positive. The change in enthalpy doesn't refer to heat as a product or activation energy. Therefore, the reaction must be endothermic.

Answer:

There are strong intermolecular forces between particles that make up liquids, but not gases.

Explanation:

Solids, liquids and gases are the three states of matter that exists. However, they possess varying properties that distinguishes them from one another. One of these properties is the strength of the intermolecular forces that hold their molecules together.

The intermolecular forces of each state of matter becomes weak in this order: solid>liquid>gas.

- Intermolecular forces in solid molecules are very strong, hence making them compact and well attached to each other.

- Intermolecular forces in liquid molecules are not too strong, hence, cannot exist in a fixed position but tend to flow.

- Intermolecular forces in gaseous molecules are very weak, hence, gases can move easily and rapidly in any given space.

Answer:

1.58 g

Explanation:

Step 1: Write the balanced equation

2 NaHCO₃ ⇒ Na₂CO₃ + H₂O + CO₂

Step 2: Calculate the moles corresponding to 2.50 g of NaHCO₃

The molar mass of NaHCO₃ is 84.01 g/mol.

2.50 g × 1 mol/84.01 g = 0.0298 mol

Step 3: Calculate the moles of Na₂CO₃ produced

The molar ratio of NaHCO₃ to Na₂CO₃ is 2:1. The moles of Na₂CO₃ produced are 1/2 × 0.0298 mol = 0.0149 mol

Step 4: Calculate the mass corresponding to 0.0149 moles of Na₂CO₃

The molar mass of Na₂CO₃ is 105.99 g/mol.

0.0149 mol × 105.99 g/mol = 1.58 g

he says he doesnt know sorry

Answer:

Following are the solution to the given points:

Explanation:

For point A:

For point B:

In point 3, the mixture was added to 100°C, which implies that the granular material flows and deforms, enabling it to become elongated. This is termed solid-state crystalline such that grains are flexible, but this material contaminates numerous little crystalline that has spheres when we cool down in point  4 polymers. It forms therefore an unstructured solid, which then in point 4 is higher in particles and less pliable in orderly atoms.

For point C:

In point 2, the specimen gets forced at room temperature to organize a huge molecule in an ordinary and crystal fashion and therefore is transparent due to highly crystalline atoms in point 2 of the PET sample.

In point 4, however, we notice how amorphous, firm but not crystalline develops. It's why light tends to disperse over many cereal limits, since many microscopic crystallines, therefore dispersion, PET in point 4 is translucent.

Answer:

4.45 atm

Explanation:

Applying,

PV = P'V'............ Equation 1

Where P = Initial pressure of the container, V = Initial volume of the container, P' = Final pressure of the container, V' = Final volume of the container.

make P the subject of the equation

P = P'V'/V........... Equation 2

From the question,

Given: V = 55.2 L, P' = 8.53 atm, V' = 28.8 L

Substitute these values into equation 2

P = (8.53×28.8)/55.2

P = 4.45 atm

Answer:

[tex]\boxed {\boxed {\sf 4.45 \ atmospheres}}[/tex]

Explanation:

We are asked to find the pressure given a change in volume. The temperature remains constant, so we are only concerned with volume and pressure. We will use Boyle's Law, which states the volume of a gas is inversely proportional to the pressure. The formula for this law is:

[tex]P_1 V_1= P_2V_2[/tex]

The initial pressure is unknown, but the volume starts at 55.2 liters.

[tex]P_1 * 55.2 \ L = P_2V_2[/tex]

The volume is reduced to 28.8 liters and the pressure is 8.53 atmospheres.

[tex]P_1 * 55.2 \ L = 8.53 \ atm * 28.8 \ L[/tex]

We are solving for the initial pressure, so we must isolate the variable P₁. It is being multiplied by 55.2 liters. The inverse operation of multiplication is division, so we divide both sides of the equation by 55.2 L.

[tex]\frac {P_1 * 55.2 \ L }{55.2 \ L}= \frac{8.53 \ atm * 28.8 \ L}{55.2 \ L}[/tex]

[tex]P_1= \frac{8.53 \ atm * 28.8 \ L}{55.2 \ L}[/tex]

The units of liters (L) cancel.

[tex]P_1= \frac{8.53 \ atm * 28.8 }{55.2}[/tex]

[tex]P_1=\frac{245.664 }{55.2 } \ atm[/tex]

[tex]P_1 = 4.45043478261 \ atm[/tex]

The original measurements of volume and pressure have 3 significant figures, so our answer must have the same. For the number we calculated, that is the hundredths place. The 0 in the thousandths place tells us to leave the 5.

[tex]P_1 \approx 4.45 \ atm[/tex]

The initial pressure inside the container is approximately 4.45 atmospheres.

A. CH4= NON POLAR

B. CH3cl= POLAR

C. CO2= NON POLAR

D.  H2O2= POLAR

E. BCl3= NON POLAR

F. H2S​= SLIGHTLY POLAR

Answer:

Magnesium - Metallic lattice

Nitrogen - Molecules

Lithium - Metallic lattice

Potassium - Metallic lattice

Explanation:

Metals exist in metallic lattices. In this lattice, metal ions are held together with a sea of electrons by strong electrostatic forces.

All metals possess this metallic lattice, hence; potassium, lithium and magnesium all consist of metal lattices.

Nitrogen is a nonmetal and consists of molecules of N2.

Explanation:

here's the answer to your question

Answer:

Option e.

Explanation:

Molarity is the concentration that indicates moles of solute in 1 L of solution.

We have another concentration, percent by mass.

Percent by mass indicates mass of solute in 100 g of solution.

Our solute is HNO₃, our solvent is water.

17.5 g of nitric acid is the mass of solute. We can convert them to moles:

17.5 g . 1mol / 63g = 0.278 moles

We do not have volume of solution. We assume the mass is 100 g because the percent by mass but we need density to state the volume.

Density = Mass / Volume

Mass / Density = Volume

Once we have the volume, we need to be sure the units is in L, to determine molarity

M = mol /L

Answer:

0.92g/mL

Explanation:

Density of a substance is calculated as follows:

Density = mass (m) ÷ volume (V)

According to this question, a rectangular piece of plastic has a width of 4.2 cm, a height of 1.9 cm and a length of 8.8 cm. Using the formula; L × W × H, the volume of the plastic can be calculated

V = L × W × H

V = 8.8 × 4.2 × 1.9

V = 70.2cm³

The mass of the plastic is 64.6g, hence, its density is:

Density = 64.6g ÷ 70.2cm³

Density of the rectangular plastic = 0.92g/cm³ or 0.92g/mL

Answer:

I think option A is right answer

Answer:

1s22s22p6

Explanation:

Neon is an element in the periodic table and has an atomic number of 10, which means it has 10 protons in its nucleus and thus since the number of protons and electrons is the same then it has 10 electrons.

Therefore, it has 2 electrons in the first energy shell and 8 electrons in the second energy shell. To elaborate further, the first shell has a single s-sub shell that contains a single s-orbital that can hold two electrons. The second energy shell has a single s-sub-shell whose s-orbital will occupy 2 electrons, and also has a p-orbital which can hold 6 electrons, making the second shell to have 8 electrons.

Answer:

Substance A has a greater molecular mass than substance B

Explanation:

The greater the mass of a substance, the slower it will travel. If the solid formed closer to substance A, it means that substance A, travelled less and that it was slower, meaning it had a greater molecular mass.

Please mark it as brainliest if it helped you

Answer:

thank you... I would say is the answer: Subtance A has a greater molecular mass than substance B.

Explanation:

thanks for posting all the comments all the time!

have a great week... stay warm from a snow storm

Answer:

the properties are:

these are all the properties but I think the two a solute needs to satisfy are

I hope this helps

Answer:

0.59 mol O₂

Explanation:

The balanced chemical equation for the decomposition of potassium chlorate (KClO₃) to produce potassium chloride (KCl) and oxygen gas (O₂) is the following:

2 KClO₃ → 2 KCl + 3 O₂

According to the equation, 3 moles of O₂ are produced from 2 moles of KClO ⇒ conversion factor: 3 mol O₂/2 mol KClO₃

Now, we calculate the number of moles of KClO₃ there is in 48.1 g, by dividing the mass into the molecular weight (Mw) of O₂:

Mw(KClO₃) = 39.1 g/mol + 35.4 g/mol + (16 g/mol x 3) = 122.5 g/mol

moles KClO₃ = mass KClO₃/Mw(KClO₃) = 48.1 g/(122.5 g/mol) = 0.3926 mol KClO₃

Finally, we multiply the moles of KClO₃ by the conversion factor to calculate the moles of O₂ produced:

0.3926 mol KClO₃ x 3 mol O₂/2 mol KClO₃ = 0.59 mol O₂