How many atoms are in 10g of Al

Answer: The molality of this solution is 1.7 m

Explanation:

Depression in freezing point:

[tex]T_f^0-T^f=i\times k_f\times m[/tex]

where,

[tex]T_f[/tex] = freezing point of solution = [tex]-70.55^0C[/tex]

[tex]T_f^0[/tex] = freezing point of pure chloroform = [tex]-63.5^0C[/tex]

[tex]k_f[/tex] = freezing point constant of benzene = [tex]4.07^0Ckg/mol[/tex]

m = molality

i = Van't Hoff factor = 1 (for non-electrolyte)

[tex]-63.5-(-70.55)^0C=1\times 4.07^0Ckg/mol\times m[/tex]

[tex]7.05=1\times 4.07^0Ckg/mol\times m[/tex]

[tex]m=1.7[/tex]

Thus the molality of this solution is 1.7 m

Answer:

1.29 g of NaCl.

Explanation:

We'll begin by writing the balanced equation for the reaction. This is given below:

HCl(aq) + NaOH(s) —> NaCl(aq) + H2O(l)

Next, we shall determine the masses of HCl and NaOH that reacted and the mass of NaCl produced from the balanced equation.

This is illustrated below:

Molar mass of HCl = 1 + 35.5 = 36.5 g/mol

Mass of HCl from the balanced equation = 1 x 36.5 = 36.5 g

Molar mass of NaOH = 23 + 16 + 1 = 40 g/mol

Mass of NaOH from the balanced equation = 1 x 40 = 40 g

Molar mass of NaCl = 23 + 35.5 = 58.5 g/mol

Mass of NaCl from the balanced equation = 1 x 58.5 = 58.5 g

Summary:

From the balanced equation above,

36.5 g of HCl reacted with 40 g of NaOH to produce 58.5 g of NaCl.

Next, we shall determine the limiting reactant.

The limiting reactant can be obtained as follow:

From the balanced equation above,

36.5 g of HCl reacted with 40 g of NaOH.

Therefore, 1.82 g of HCl will react with = (1.82 x 40)/36.5 = 1.99 g of NaOH

From the calculations made above,

We can see that it will take a higher mass of NaOH i.e 1.99 g than what was given i.e 0.88 g to react completely with 1.82 g of HCl.

Therefore, NaOH is the limiting reactant and HCl is the excess reactant.

Finally, we shall determine the maximum mass of NaCl produced from the reaction.

In this case the limiting reactant will be used as it will produce the maximum mass of the products since all of it were consumed in the reaction.

The limiting reactant is NaOH and the maximum mass of NaCl produced can be obtained as follow:

From the balanced equation above,

40 g of NaOH reacted to produce 58.5 g of NaCl.

Therefore, 0.88 g of NaOH will react to produce = (0.88 x 58.5)/40 = 1.29 g of NaCl.

Therefore, 1.29 g of NaCl were produced from the reaction.

Answer:

D. 48 N down

Explanation:

Given that:

Mass of climber = 85 kg, Tension on rope = 785 N, acceleration due to gravity = 9.8 m/s²

To calculate the net force on the climber, we need to first calculate the weight of the climber. Since the climber is affected by the earth gravity, the weight of the climber is the product of his mass and the acceleration due to gravity, therefore:

Weight = mass × acceleration due to gravity = 85 kg × 9.8 m/s² = 833 N

The weight of the climber is acting downwards while tension on the rope is acting upwards, therefore:

Net force on the climber = 785 N - 833 N = - 48 N

This means that the net force on the climber is 48 N downwards

Answer:

48 N down

Explanation:

Ayepecks

Answer:

3850g

Explanation:

Solubility is the amount of solute dissolved in a solvent.

Solubility is mass of solute÷mass of solvent

The solvent is 35grams

Solute?

Solubility of solute is 110

110=x/35

= 110 × 35

The amount of residue solute is 3850g

Answer:

Option D. T

Explanation:

Enthalpy change (ΔH) is simply the difference between the heat content of the product (Hp) and the heat content of the reactant (Hr). Mathematically, it is expressed as:

Enthalpy change (ΔH) = Heat of product (Hp) – heat of reactant (Hr)

ΔH = Hp – Hr

From the diagram given above, the difference between the heat content of product and the heat content of reactant is T.

Therefore, the enthalpy change of the reaction is T.

Answer:

27. Element (Because it contains all same atoms)

28. Compound (It contains atoms held together through chemical bonds)

29. Element (it contains all same atoms)

33. Mixture (It contains different atoms but they are not held together through chemical means)

34. Compound (Different atoms held together through chemical means)

35. Mixture (Mixture of elements and compounds)

30. Element (it contains all same atoms)

31. Mixture (Mixture of elements and compounds)

32. Element (Contain all same atoms although held together through chemical means they are not compounds)

Answer:

See the answer below

Explanation:

In chemistry, indicators are substances that are capable of changing colors with respect to the pH. Each indicator has its characteristic color in acidic pH and another characteristic color in alkaline pH.

Methyl orange indicator appears red in acidic solution and yellow in basic solutions. Phenolphthalein is usually colorless in acidic solutions and appears pink in basic solutions. A red litmus paper will turn blue in alkaline solutions while a blue litmus paper will turn red in acidic solutions.

Answer: I just took the test, the answer is A.

Explanation:

Explanation:

The principle used in the preparation of these salts is to dissolve

the cystine in an alcoholic alkali solution to which just sufficient

water to effect solution has been added, and, after filtering from

excess cystine, to precipitate the salt by addition of a suitable

indifferent solvent. While various solvents, such as acetone,

ether, or large amounts of alcohol caused precipitations, these were

either oily or amorphous. Only acetonitrile was found to possess

the power of initiating regular crystallization in the salt solutions.

While the solutions of the different salts require different amounts

of the solvent for complete precipitation, a partial substitution of

absolute ether for acetonitrile was found expedient in the case

of the most soluble of the salts, the K salt.

Answer:

It is simply a process of forming crystal.

Explanation:            When salt is heated and dissolve in the liquid mainly water then its called saturated solution. When we further add salt and increase heat in order to dissolve it then it forcibly dissolve in liquid it's called supersaturated solution. After we slowly cool down the temperature then the salt we have put in supersaturated solution arises in the form of crystal. Hence its called crystalization.

Answer:

Option D. AlCl₃, MgC₂

Explanation:

We need to dissociate all the salts, to determine the i. (Van't Hoff factor).

The salt who has the highest value, will be the better conductor of electricity

CsCl  → Cs⁺  +  Cl⁻   i = 2

CaCl → Ca²⁺ +  Cl⁻   i = 2

CaS → Ca²⁺ +  S⁻²    i = 2

Li₂S → 2Li⁺  +  S⁻²    i = 3

KBr →  K⁺  +  Br⁻       i = 2

AlCl₃ →  Al³⁺ + 3Cl⁻   i = 4

MgC₂  →  Mg²⁺  +  2C⁻   i = 3

KI  →  K⁺  +  I⁻     i = 2

K₂S  →  2K⁺  + S⁻²   i = 3

The biggest i, is in pair D.

Answer:

Look at the Screenshot!!!

Explanation:

Got it right on Odessyware ;) Have a nice day!!!!!

Answer:

See below

Explanation:

Ammonium [tex](NH_{4}^+)[/tex] is not a molecular ion because it is just a poly-atomic ion. A molecular ion has a "negative or positive charge" as a whole but the positive charge on here is not on the whole. So, it is a poly-atomic ion and not molecular ion.

The computers that help control the machines in the factory

Answer:

The correct option is;

C. Old Age River

Explanation:

Among the three stages of  the development of a river, which are the youthful, mature, and old age stages, the old age river is least dynamic

The water is very slow moving  with a low gradient and lesser erosive power to alter the landscape which results in the appearance of flood planes

Examples of old age rivers include, lower Ganges, lower Nile, Indus, and Yellow rivers

Old age rivers are characterized by a broad shape, with a wide flood plane, a very gentle gradient and the water current is low.

Answer:c

Explanation:

old age river

Answer:

carbohydrates are energy giving foods that warm the body and could be in different forms

Answer and Explanation:

Carbohydrates are a type of biomolecule that the body uses primarily for energy and/or structure. They usually consist of the elements carbon (C), hydrogen (H), and oxygen (O) in a 1 : 2 : 1 ratio. For example, glucose, a carbohydrate, is [tex]C_6H_{12}O_6[/tex].

Monomers of carbohydrates are called monosaccharides, and polymers are called disaccharides if two monosaccharides are combined and polysaccharides if more than two monosaccharides are put together.

Examples of carbohydrates are sugars, starches, cellulose, lactose, sucrose, etc.

Answer:

266 liters Carbon iv oxide will be formed

Explanation:

The first thing we need to do here is to calculate the number of moles of oxygen reacted.

This can be calculated using the ideal gas equation;

Mathematically;

PV = nRT

From the question;

P = pressure = 10.5 atm

V = volume = 400 liters

n = number of moles = ?

T = temperature = 125 + 273 = 398K

R = molar gas constant = 0.0821 L•atm•K^-1•mol^-1

Substituting these values, we have ;

n = PV/RT

n = (10.25 * 400)/(398 * 0.0821) = 125 moles

From the question;

15 moles oxygen gave 10 moles CO2

125 moles oxygen will give x moles CO2

x = (125 * 10)/15 = 83 moles

Now, we want to know the volume of CO2, present in 83 moles using the given reaction conditions.

Mathematically;

PV = nRT

V = nRT/P

= (83 * 0.0821 * 398)/10.25 = 265.65 which is approximately 266 Liters

Answer:

because the water/air needs to be pumped out.

Explanation:

hoped this helped! (just give it a 1 star if it didn't)

Answer:

A

Explanation:

the increase in the temperature let's the particles to collide more so it increases the rate of reaction.

Answer:

I think the answer is option A.

Explanation:

Because when the temperature increases, the kinetic enegry increases which creates the effective collisions which lets the chemical to react.

Hope it helps..

Answer:

Difference in temperature.

Explanation:

Conduction is the movement of heat energy through a substance or from one substance to another by direct contact of atoms and molecules. Heat moves directly from one molecule to another. The heat energy speeds up the movement of the atoms and they collide with other molecules setting them into faster motion.

Answer:

After the reaction, there will 0.60 g of magnesium oxide and 0.25 g of oxygen gas present in the tube

Explanation:

Equation of the reaction between magnesium and oxygen is given as follows:

2Mg(s) + O₂(g) ---> 2MgO(s)

From the equation of reaction, 2 moles of magnesium reacts with i mole of oxygen gas to produce 1 mole of magnesium oxide

molar mass of magnesium is 24.0 g; molar mass of oxygen gas = 32.0 g; molar mass of magnesium oxide = 40.0 g

Therefore 24 g of magnesium reacts with 32 g of oxygen gas

I.00 g of magnesium will react with (24.0 / 32.0) * 1.00 g of oxygen = 0.75 g of oxygen gas.

Therefore, magnesium is the limiting reagent. Once it is used up, the reaction will stop and the excess oxygen will be left in the tube together with the product, magnesium oxide.

mass of excess oxygen = 1.00 - 0.75 = 0.25 g

mass of magnesium oxide formed = (24.0 / 40.0 g) * 1 = 0.60 g

Answer: Thus concentration of [tex]Ca(OH)_2[/tex] in [tex]mol/dm^3[/tex]  is 0.011 and in [tex]g/dm^3[/tex] is 0.814

Explanation:

To calculate the concentration of [tex]Ca(OH)_2[/tex], we use the equation given by neutralization reaction:

[tex]n_1M_1V_1=n_2M_2V_2[/tex]

where,

[tex]n_1,M_1\text{ and }V_1[/tex] are the n-factor, molarity and volume of acid which is [tex]HCl[/tex]

[tex]n_2,M_2\text{ and }V_2[/tex] are the n-factor, molarity and volume of base which is [tex]Ca(OH)_2[/tex]

We are given:

[tex]n_1=1\\M_1=0.06mol/dm^3\\V_1=11cm^3=0.011dm^3\\n_2=2\\M_2=?\\V_2=30cm^3=0.030dm^3[/tex]         [tex]1cm^3=0.001dm^3[/tex]

Putting values in above equation, we get:

[tex]1\times 0.06mol/dm^3\times 0.011dm^3=2\times M_2\times 0.030dm^3\\\\M_2=0.011mol/dm^3[/tex]

The concentration in [tex]g/dm^3[/tex] is [tex]0.011mol/dm^3\times 74g/mol=0.814g/dm^3[/tex]

Thus concentration of [tex]Ca(OH)_2[/tex] is [tex]0.011mol/dm^3[/tex] and [tex]0.814g/dm^3[/tex]

Answer:

d

Explanation:

d

Answer:

Mg  

Explanation:

The standard reduction potentials are

                                              E°/V

Au³⁺(aq ) + 3e⁻  ⟶  Au(s);     1.42

Hg²⁺(aq)  + 2e⁻  ⟶  Hg(l);     0.85

Ag⁺(aq)    +   e⁻  ⟶  Ag(s);    0.80

Cu²⁺(aq)   + 2e⁻ ⟶  Cu(s);   0.34

Mg2+(aq) + 2e- ⟶  Mg(s);   -2.38

The more negative the standard reduction potential, the stronger the metal is as a reducing agent.

Mg is the only metal with a standard reduction potential lower than that of Cu, so

Only Mg will react spontaneously with Cu²⁺.

Answer:

B. Mg

Explanation:

Explanation:

ascorbic acid is lemon

lemon contain ascorbic acid....

it is organic acid.....

Answer:

HeyA ❤

Let us consider the mass of oxygen as 1 g.

Mass of lead obtained from yellow oxide = 3.45 g – 0.24 g = 3.21 g

Mass of oxygen = 0.24 g

The mass of lead that combines with 0.24 g of oxygen = 3.21 g

Therefore, mass of lead that combines with 1 g of oxygen = 3.21/ 0.24 = 13.4 g

Mass of lead obtained from brown oxide = 1.227 g – 0.16 g = 1.067

Mass of oxygen = 0.16g

The mass of lead that combines with 0.16 g of oxygen = 1.067 g

Therefore, mass of lead that combines with 1 g of oxygen = 1.067/ 0.16 = 6.66 g

Now, ratio of masses of lead which combines with a fixed mass of oxygen = 13.4 : 6.66

= 2 :1

Thus, masses of lead which combine with the fixed mass of oxygen are in the ratio of (2:1) i.e. small whole numbers.

Hence, the law of multiple proportions is illustrated.

Follow meehhhh Piper ❤

Answer:

The molecules move more slowly and their average kinetic energy decreases

Explanation:

The increased temperature meant that the atoms in liquid had a greater average energy of motion so as the temperature decreases the reaction would be inverse.

The branch of science which deals with the chemicals bond is called chemistry.

The correct option is B.

The energy which is produced by the motion of the particles is called kinetic energy. Temperature increases the motion of the particles. So, the kinetic energy increases when the temperature rises.

According to the question, the temperature of the water decreases therefore the kinetic energy decreases.

Hence, the correct option is B that is the molecules move more slowly and their average kinetic energy decreases.

For more information, refer to the link:-

https://brainly.com/question/25026730

Answer:

B)  40 individuals emigrate, 0 individuals die, 10 individuals are born, 28 individuals immigrate

Explanation:

its right on edg2020 :)

Answer: N2(g) + 3H2(g)- >2NH3(g) denotes a negative entropy change.

Explanation:

Entropy is defined as the extent of disorder in a system. The degree of entropy is more in a gas and less in a solid.

Here, 1st reaction produces ammonia from nitrogen and hydrogen. We can see that four moles of gases produces 2 moles of gaseous product. So the degree of disorder in the system is decreasing. So the entropy is also decreasing.

mg has a 2 in its valence shell

it will become mgcl2

. . . .

: Cl -------- Mg ------ Cl :

. . . .

Answer:

MgO

Explanation:

Mg, which is magnesium, is considered a metal, when paired with Oxygen, which is a gas, it creates magnesium oxide, and the formula itself is a pairing of a metal with a nonmetal

Answer:

[tex]\boxed{MgO}[/tex]

Explanation:

Metals are red, nonmetals are blue, and metalloids are yellow in the attached file.

Using this table, you can see that Mg is a metal and O is a nonmetal, which fits the question criteria.

Hope this helps!