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.
ANSWER:

True

False

Answer:

By how many times would you expect Al2(SO4)3 to depress the F.P of water compared to sucrose C12H22011 ?.

Explanation:

The freezing point of a pure solvent decreases further by adding a nonvolatile solute.

This is called depression in freezing point.

When an ionic solute is dissolved then the depression in the freezing point is proportional to the number of ions present in the solution.

In aluminum sulfate, there are five ions formed as shown below:

[tex]Al_2(SO_4)_3(aq)->2Al^3^+(aq)+3SO_4^2^-(aq)[/tex]

But sucrose is a covalent compound and it does not undergo dissociation.

Hence, aluminum sulfate decreases the freezing point of water by five times compared to sucrose.

Explanation:

Answer:

Principles of green chemistry:

• Prevent wastes rather than treat them.

• Incorporates all raw materials into the final product.

• Use of synthetic methods.

• To design chemical products to reduce toxicity.

• Use of energy-efficient processes.

• Use of renewable raw materials.

• Reuse chemical intermediates to reduce waste.

• Improve health and safety for staff and customers.

• Cleaner production technologies.

Green chemistry principles can be applied to radioactive wastes by:

• We should choose reagents and procedures that lessen the toxicity and volume of all the wastes. We need to design experiments that radioactive wastes that are produced separately from biologically or chemically hazardous wastes if flexible.

• Substitutes with short-lived radionuclides were feasible.

• Reduce the activity and volumes of wastes generated.

• Limit the number of users of radioactive materials.

• Replace hazardous or mixed wastes.

• Non-radioactive wastes will not be mixed with radioactive wastes. If it is not done then the volume of wastes increases.

Answer:

C. Products have higher potential energy, and the reaction is endothermic.

Answer:

The volume of the gas is fixed and will not change.

Explanation:

The volume of the gas will not change because there is no change in temperature. Temperature increases the volume of gases enclosed in a container.

Answer:

.

Elements are arranged from left to right and top to bottom in the order of their increasing atomic numbers. Thus,

Elements in the same group will have the same valence electron configuration and hence, similar chemical properties.

Whereas, elements in the same period will have an increasing order of valence electrons. Therefore, as the energy level of the atom increases, the number of energy sub-levels per energy level increases.

The first 94 elements of the periodic table are naturally occurring, while the rest from 95 to 118 have only been synthesized in laboratories or nuclear reactors.

The modern periodic table, the one we use now, is a new and improved version of certain models put forth by scientists in the 19th and 20th century. Dimitri Mendeleev put forward his periodic table based on the findings of some scientists before him like John Newlands and Antoine-Laurent de Lavoisier. However, Mendeleev is given sole credit for his development of the periodic table.

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:

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.

Explanation:

a) Since this is a double displacement reaction, we write the balanced equation as

[tex]2AgNO_3(aq) + CaCl_2(aq) \\ \rightarrow 2AgCl(s) + Ca(NO_3)_2(aq)[/tex]

b) Next we find the number of moles of AgNO3 in the solution.

[tex](0.005\:\text{L})(0.500\:M\:AgNO_3) \\ = 0.0025\:\text{mol}\:AgNO_3[/tex]

Next, use the molar ratio to find the necessary amount of CaCl2 to react with the AgNO3:

[tex]0.0025\:\text{mol}\:AgNO_3× \left(\dfrac{1\:\text{mol}\:CaCl_2}{2\:\text{mol}\:AgNO_3} \right)[/tex]

[tex]= 0.00125\:\text{mol}\:CaCl_2[/tex]

The volume of 0.500 M solution of CaCl2 necessary to react all of the given AgNO_3 is then

[tex]V = \dfrac{0.00125\:\text{mol}\:CaCl_2}{0.500\:\text{M}\:CaCl_2}[/tex]

[tex]= 0.0025\:\text{L} = 2.5\:\text{mL}\:CaCl_2[/tex]

c) The theoretical yield can then be calculated as

[tex]0.0025\:\text{mol}\:AgNO_3 × \left(\dfrac{2\:\text{mol}\:AgCl}{2\:\text{mol}\:AgNO_3} \right)[/tex]

[tex]= 0.0025\:\text{mol}\:AgCl[/tex]

Converting this amount of AgCl into grams, we get

[tex]0.0025\:\text{mol}\:AgCl × \left(\dfrac{143.32\:\text{g}\:AgCl}{1\:\text{mol}\:AgCl} \right)[/tex]

[tex]= 0.358\:\text{g}\:AgCl[/tex]

Answer:

Towards the big bully

Explanation:

If a big bully and a small child are involved in a thug of war, it is clear that the bully is stronger than the child and he/she will pull the rope used in the thug of war with a greater force.

By so doing, the ball attached at the centre of the rope will naturally be drawn towards the stronger bully.

Answer:

Substrate

Explanation:

In biochemical sciences, a substrate is a substance that is acted upon by an enzyme to yield a product. Enzymes are known for catalyzing biochemical reactions. The substances that are usually worked with during this catalytic process are termed as SUBSTRATES.

Substrates, which are usually changed during the process, binds to the active site on the enzyme and form an enzyme-substrate complex.

According to this question, pyruvate is converted to lactate in a reaction that is catalyzed by the enzyme lactate dehydrogenase. This means that the compound on which the enzyme works, pyruvate, is called the SUBSTRATE.

Answer:

Option A is correct, there will be no N2 left in the flask

Explanation:

Step 1 : Data given

Number of moles of N2 = 135 mmol = 0.135 mol

Number of moles of H2 = 405 mmol = 0.405 mol

Step 2: The reaction

N2(g)+3H2(g)→2NH3(g)

Step 3:

For 1 mol N2 we need 3 moles H2 to produce 2 moles NH3

Both will completely react. There is no limiting reactant.

There will be produce 0.270 moles NH3.

Option A is correct, there will be no N2 left in the flask

Complete question is;

Identify the type of reaction in the chemical reaction below:

2P205 ➡️ 4P + 502

single replacement

synthesis

decomposition

combustion

double replacement

Answer:

Decomposition

Explanation:

We. An see in the question that the compound 2P205 is broken down into simpler substances which are phosphorus (P) and oxygen (O).

Now, this is a decomposition reaction because a decomposition reaction is one in which a compound is broken down into simpler substances

C. It can help us track how quickly element of the climate are changing

Answer:

Toluene

Explanation:

This compound is called toluene.

It is a phenyl group where it is bonded a methyl.

It is an aromatic compound.

IUPAC name can be, Methylbenzene.

As an organic compound it can not be dissolved in water.

This can be a reaction of synthesis:

C₆H₅H + CH₃Cl → C₆H₅CH₃ + HCl

Answer:

These batteries are constructed of several single cells connected in series each cell produces approximately 2.1 volts. ... A battery cell consists of two lead plates a positive plate covered with a paste of lead dioxide and a negative made of sponge lead, with an insulating material (separator) in between.

Explanation:

In the formula of [tex]CaCl_2[/tex] we can see that there are 2mol Cl in 1 molecule of CaCl2. So, now we can do some math to find out how many mol of Cl there are in 1.9mol CaCl2!

[tex]1.9molCaCl_2*\frac{2molCl}{1molCaCl_2}[/tex]

So, there are 3.8mol Cl

Answer:

The explanation as per the given query is presented in the following paragraph.

Explanation:

Thus the above is the correct explanation.

The measured absorbance will be higher, thereby creating systematic error.

In conclusion, the measured absorbance will be higher, thereby creating systematic error.

Learn more in:

https://brainly.com/question/14919298

Answer:

41264 g of CO₂

Explanation:

Combustion reaction is:

C₃H₈ + 5O₂ →  3CO₂  +  4H₂O

1 mol of propane react to 5 moles of oxygen in order to proudce 3 moles of carbon dioxide and 4 moles of water.

In a combustion reaction, our reactant reacts to oxygen and the products are always CO₂ and water.

We have the volume of propane but we need moles of it, so we need to apply density.

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

Density of propane is: 493 g/L

Mass of propane is 493 g/L . 27.9L = 13754.7 g

We convert mass to moles: 13754.7 g . 1 mol/ 44g = 312.6 moles

According to reaction, 1 mol of propane can produce 3 moles of CO₂

Our 312.6 moles will produce 312.6 . 3 = 937.8 moles

We convert moles to mass: 937.8 mol . 44 g/mol = 41264 g

The forces in gases are weaker than forces in solids and liquids.

Because they have more kinetic energy that overcomes the force of attraction.

Answer:

66.7%

Explanation:

Step 1: Write the balanced equation

CHCl₃ + Cl₂ ⇒ CCl₄ + HCl

Step 2: Calculate the theoretical yield of CCl₄ from 11.9 g of CHCl₃

According to the balanced equation, the mass ratio of CHCl₃ to CCl₄ is 119.38:153.82.

11.9 g CHCl₃ × 153.82 g CCl₄/119.38 g CHCl₃ = 15.3 g CCl₄

Step 3: Calculate the percent yield of CCl₄

Given the experimental yield of CCl₄ is 10.2 g, we can calculate the percent yield using the following expression.

%yield = (exp yield/theo yield) × 100%

%yield = (10.2 g/15.3 g) × 100% = 66.7%

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:

Fill in the blanks with each titration term with its definition.

a. Solution of an unknown concentration that has another solution slowly added to it ________________

b. Process of slowly adding a solution to react with another solution and determine the concentration of one of the solutions based on the reaction between them ______________

c. A reagent added to the analyte solution that changes color when the reaction is complete ______________

d. Glassware that allows a solution to be precisely and slowly added to another solution _____________

e. Solution of known concentration that is slowly added to a solution of unknown concentration ________________

f. When the required amount of one solution has been added to the second solution to complete the reaction ____________

Explanation:

a. Solution of an unknown concentration that has another solution slowly added to it is called analyte.

b. Process of slowly adding a solution to react with another solution and determine the concentration of one of the solutions based on the reaction between them is called titration.

c. A reagent added to the analyte solution that changes color when the reaction is complete is called an indicator.

d. Glassware that allows a solution to be precisely and slowly added to another solution is called a pipette.

e. Solution of known concentration that is slowly added to a solution of unknown concentration is called titrant.

f. When the required amount of one solution has been added to the second solution to complete the reaction is called neutralization.

Answer:

La temperatura final del sistema es 1029,346 °C.

Explanation:

Asumamos que el sistema conformado por el cobre y el estaño no tiene interacciones con sus alrededores. Por la Primera Ley de la Termodinámica, el cobre cede calor al estaño con tal de alcanzar el equilibrio térmico. El cobre se encuentra inicialmente en su punto de fusión, mientras que el estaño está por encima de ese punto, de modo que la transferencia de calor es esencialmente sensible:

[tex]m_{Cu}\cdot c_{Cu}\cdot (T-T_{Cu}) = m_{Sn}\cdot c_{Sn}\cdot (T_{Sn}-T)[/tex]

[tex](m_{Cu}\cdot c_{Cu} + m_{Sn}\cdot c_{Sn})\cdot T = m_{Sn}\cdot c_{Sn}\cdot T_{Sn} + m_{Cu}\cdot c_{Cu}\cdot T_{Cu}[/tex]

[tex]T = \frac{m_{Sn}\cdot c_{Sn}\cdot T_{Sn}+m_{Cu}\cdot c_{Cu}\cdot T_{Cu}}{m_{Cu}\cdot c_{Cu}+m_{Sn}\cdot c_{Sn}}[/tex] (1)

Donde:

[tex]m_{Sn}[/tex] - Masa del estaño, en gramos.

[tex]m_{Cu}[/tex] - Masa del cobre, en gramos.

[tex]c_{Sn}[/tex] - Calor específico del estaño, en calorías por gramo-grados Celsius.

[tex]c_{Cu}[/tex] - Calor específico del cobre, en calorías por gramo-grados Celsius.

[tex]T_{Sn}[/tex] - Temperatura inicial del estaño, en grados Celsius.

[tex]T_{Cu}[/tex] - Temperatura inicial del cobre, en grados Celsius.

Si sabemos que [tex]m_{Cu} = 150\,g[/tex], [tex]m_{Sn} = 35\,g[/tex], [tex]c_{Cu} = 0,093\,\frac{cal}{g\cdot ^{\circ}C}[/tex], [tex]c_{Sn} = 0,060\,\frac{cal}{g\cdot ^{\circ}C}[/tex], [tex]T_{Sn} = 560\,^{\circ}C[/tex] y [tex]T_{Cu} = 1100\,^{\circ}C[/tex], entonces la temperatura final del sistema es:

[tex]T = \frac{(35\,g)\cdot \left(0,060\,\frac{cal}{g\cdot ^{\circ}C} \right)\cdot (560\,^{\circ}C)+(150\,g)\cdot \left(0,093\,\frac{cal}{g\cdot ^{\circ}C} \right)\cdot (1100\,^{\circ}C)}{(35\,g)\cdot \left(0,060\,\frac{cal}{g\cdot ^{\circ}C} \right)+(150\,g)\cdot \left(0,093\,\frac{cal}{g\cdot ^{\circ}C} \right)}[/tex]

[tex]T = 1029,346\,^{\circ}C[/tex]

La temperatura final del sistema es 1029,346 °C.

Answer:

0.64 m

Explanation:

Given that;

1L = 0.001 cubic metre

Then;

263 L = 263 L × 0.001 cubic metre/1L

= 0.263 cubic metre

Volume of a cube = l^3

l= 3√V

l= 3√0.263 cubic metre

l= 0.64 m

Answer:

The solution is 0.450 M. How many mL are needed?

- 0.667 mL

Explanation:

Answer:

Following are the solution to the given question:

Explanation:

For question a:

It is prevented that the atmospheric [tex]CO_2[/tex] through dissolving in the solution and make carbonic acid [tex](H_2CO_3)[/tex] which reacts with the [tex]NaOH:[/tex]

[tex]CO_2+ H_20\to H_2CO_3\\\\H_2CO_3 + NaOH \to NaHCO_3 +H_2O\\\\H_2CO_3 + 2 NaOH \to Na_2CO_3 + 2H_2O\\\\[/tex]

For question b:

For this, the [tex]NaOH[/tex] reacts with the dissolved [tex]CO_2[/tex]  so, the molarity of the [tex]NaOH[/tex] will be decreased.

For question C:

In this, the Phenolphthalein is pink in the basic solution[tex](high \ pH)[/tex] and colorless throughout the acidic solution[tex](low\ pH)[/tex].

if the solution is exposed  from the atmosphere, the [tex]CO_2[/tex] is from the air dissolving in the solution, and making the [tex]H_2CO_3[/tex] that gives the [tex]H^{+}\ ions[/tex]

[tex]\to[/tex] lower pH.

[tex]\to[/tex] colorless phenolphthalein  

For question D:

[tex]Ba(OH)_2 + 2 HNO_3 \to Ba(NO_3)_2+ 2H_2O\\\\[/tex]

Calculating the moles of[tex]HNO_3 = volume \times \text{concentration of} HNO_3\\\\[/tex]

                                                      [tex]= \frac{25}{1000} \times 0.200\\\\= 0.005\ mol\\\\[/tex]

Calculating the moles of  [tex]Ba(OH)_2= \frac{1}{2} \times\text{moles of}\ HNO_3\\\\[/tex]

                                [tex]=\frac{1}{2} \times 0.005\\\\= 0.0025 \ mol\\\\[/tex]

Calculating the volume of [tex]Ba(OH)_2=\frac{moles}{concentration\ of\ Ba(OH)_2}[/tex]

                                   [tex]=\frac{0.0025}{0.0293}\\\\=0.08532\ L\\\\= 85.32 \ mL\\\\= 85.3\ mL[/tex]

Answer:

Molecules of O₂F₂ = mass of O₂F₂ × (1 mole O₂F₂ / 70 g O₂F₂) × (6.02 × 10²³ molecules / one mole of O₂F₂)

Explanation:

The Avogadros constant gives the the number of specified entities in one mole of a substance. One mole of any substance contains 6.02 × 10²³ particles. Therefore, one mole of O₂F₂ contains 6.02 × 10²³ molecules.

Also, the molar mass of a substance is the mass in grams of one mole of that substance. It is obtained by summing the relative atomic masses of all the atoms of the elements in the substance. For O₂F₂, the molar mass = (2 × 16 + 2 × 19) g/mol = 70 g/mol

Converting to molecules of O₂F₂;

To convert from grams of a substance to molecules of that substance, multiply by the ratio of one mole and mass of one mole, and then by the number of molecules per mole.

Molecules of A = mass of A × (1 mole / mass of one mole) × (6.02 × 10²³ molecules / 1 mole)

Therefore,Molecules of O₂F₂ = mass of O₂F₂ × (1 mole O₂F₂ / 70 g O₂F₂) × (6.02 × 10²³ molecules /one mole of O₂F₂)

Answer:

72.96 of water produce by 45.4 L of oxygen at STP.

Explanation:

[tex]H_2+\frac{1}{2}O_2\rightarrow H_2O[/tex]

1 mole of oxygen=22.4 L at STP

[tex]\frac{1}{2}[/tex]\mole of oxygen=22.4/2=11.2 L

11.2 L of oxygen required to produce water=1 mole

1 L of oxygen required to produce water=1/11.2 mole

45.4 L of oxygen required to produce water=[tex]\frac{1}{11.2}\times 45.4[/tex]

45.4 L of oxygen required to produce water=[tex]\frac{45.4}{11.2}[/tex]moles

1 mole of water=18 g

[tex]\frac{45.4}{11.2}[/tex]moles of water=[tex]18\times \frac{45.4}{11.2}[/tex]

[tex]\frac{45.4}{11.2}[/tex]moles of water=72.96 g

Hence, 72.96 of water produce by 45.4 L of oxygen at STP.