What is meant by “normal” when you are asked for normal boiling and melting points?

Answers

Answer 1

Answer:

Normal boiling point is the temperature at which a liquid boils at 1 atmosphere of pressure.

Explanation:


Related Questions

Why are prefixes often added to SI units?

Answers

Answer: SI prefixes are used to form decimal multiples and submultiples of SI units. They should be used to avoid very large or very small numeric values.

Explanation: ^^^

Why would it be more comfortable to walk on hot beach sand in flip-flops
than without them?
O A. Thermal insulation is blocked by the flip-flops.
B. Convection warming is blocked by the flip-flops.
C. Radiation warming is blocked by the flip-flops.
O D. Thermal conduction is blocked by the flip-flops.

Answers

Answer:

D. Thermal conduction is blocked by the flip-flops.

Explanation:

Convection is a process of heat transfer which involves fluids( liquid or gas). This however rules convection out of the answer.

Radiation involves heat transfer from the sun to bodies on earth.

Conduction involves heat transfer between two solid bodies. Hot beach sand and flip-flops are solid bodies which validates thermal(heat) conduction.

How many moles are there in 500cm3 of a 0.5mol/dm³ solution of sulfuric acid?

Answers

Answer:

0.25moles

Explanation:

There are 1000[tex]cm^{3}[/tex] for 1[tex]dm^{3}[/tex]

Therefore in 1000[tex]cm^{3}[/tex] of 0.5 mol/[tex]dm^{3}[/tex] solution has = 0.5 moles

Therefore 500[tex]cm^{3}[/tex] contains = 0.5/1000 x 500 = 0.25moles

The number of moles of sulfuric acid in 0.5 mol/dm³ solution is equal to 0.25 mol.

What is the molarity?

The concentration of the solution can be determined as the number of moles of a solute in per unit volume of a solution is known as molarity or molar concentration.

The Molarity of the solution is calculated in the following formula:

Molarity (M) = Moles (n)/Volume of the Solution (in L)

Now if we have to find the number of moles of solute in the solution, the formula becomes:

Number of moles of solute (n) = Molarity (M) × Volume of the Solution

Given, the concentration of the sulfuric acid solution = 0.5 mol/dm³

The volume of the solution, V = 500 cm³

As we know, 1 dm³ = 10³ cm³, the volume of solution = 0.5 dm³

The number of moles of the sulfuric acid = M × V

= 0.5 × 0.5 = 0.25 mol

Therefore, 0.25 moles of sulfuric acid in 500cm3 of a 0.5mol/dm³ solution of sulfuric acid.

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Connie was making sodium chloride by adding an acid to an alkali. She followed the progress of the reaction with a pH sensor .What else could she have used to detect when the reaction was complete?

Answers

What Connie could have used to detect when the chemical reaction was complete is an: acid-base indicator.

A chemical reaction is a chemical process that involves the continuous rearrangement (transformation) of either the ionic, atomic or molecular structure of a chemical element through the breakdown and formation of chemical bonds, in order to produce a chemical compound.

When a strong acid such as Hydrogen chloride (HCl) react with a strong alkali such as Sodium hydroxide (NaOH), it gives rise to the formation of Sodium chloride (NaCl) and Water ([tex]H_2O[/tex]);

                       [tex]HCl + NaOH[/tex] ----> [tex]NaCl + H_2O[/tex]

The progress of the above chemical reaction can be followed by using a pH sensor and the final pH of a strong acid and strong base is seven (7), meaning it is neutral.

However, Connie could make use of an acid-base indicator to detect when the chemical reaction is complete.

An acid-base indicator can be defined as a chemical substance that changes color with respect to the pH (hydrogen ion concentration) of a solution or chemical reaction. Some examples of an acid-base indicator are:

Litmus paper.Methyl red.Red cabbage juice.Bromothymol blue.Methyl orange.Phenolphthalein.

In conclusion, an acid-base indicator is typically used for detecting when a chemical reaction between an acid and an alkali is complete.

Read more here: https://brainly.com/question/16284171

Answer:When a strong acid such as Hydrogen chloride (HCl) react with a strong alkali such as Sodium hydroxide (NaOH), it gives rise to the formation of Sodium chloride (NaCl) and Water ();

---->

Explanation:

Which of the following contribute(s) to most of the mass of an atom?
O A) Protons and electrons
B) Protons only
C) Protons and neutrons
OD) Neutrons only

Answers

Answer:

C) protons and neutrons

Explanation:

im pretty sure it is c

C) protons and neutrons

to the
of the substances.
DONE

Answers

Answer

what do you mean?

Explanation:

im confused

Answer:

Sorry. I don't understand

Explanation:

20 points!! Please help me! Will mark Brainliest!! complete the following word equations:) also write the balanced equation, full ionic equation, and net ionic equation. Also include the states:)

a) zinc nitrate + calcium sulphide—>

b) potassium + calcium chloride—>

Answers

they are both part of the reactivity series. check out the reactivity series and u should be able to do it. it’s basically displacement

what is the answer to y=1/2-x+1​

Answers

Answer:

X= -Y + 2/2     Y=-X + 3/2

Explanation:

I don't know how to simplify it anymore. You would get x=-y+3/2 and y=-x+3/2

Answer:

Explanation:

(-1/2,1)

How many moles of ethylene glycol must be added to 1 kg of water to make a solution with a freezing point of -2.4°C? The freezing point depression constant for water is 1.86°C•kg/mol. What is the molality of the solution?

Answers

Answer: 1.29 moles of ethylene glycol must be added to 1 kg of water to make a solution with a freezing point of -2.4°C. Molality of solution is 1.29 m.

Explanation:

Depression in freezing point is given by:

[tex]\Delta T_f=i\times K_f\times m[/tex]

[tex]\Delta T_f=T_f^0-T_f=(0-(-2.4))^0C=2.4^0C[/tex] = Depression in freezing point

i= vant hoff factor (for non electrolyte , i = 1)

[tex]K_f[/tex] = freezing point constant for water= [tex]1.86^0C/kgmol[/tex]

m= molality =[tex]\frac{\text{moles of solute}}{\text{weight of solvent in kg}}[/tex]

m= molality =[tex]\frac{x}{1kg}[/tex]

[tex]2.4^0C=1\times 1.86^0C/kgmol\times \frac{x}{1kg}[/tex]

[tex]x=1.29[/tex]

Molality = [tex]\frac{\text{moles of solute}}{\text {weight of solvent in kg}}=\frac{1.29mol}{1kg}=1.29m[/tex]

Thus 1.29 moles of ethylene glycol must be added to 1 kg of water to make a solution with a freezing point of -2.4°C. Molality of solution is 1.29 m.

Answer:

1) C (m=T f/Kf)

2) 2.4 C

3) 1.3 m

4) 1.3 moles

Explanation:

This is correct on ed

How many liters of hydrogen gas is produced from 3.712 g of magnesium with 104.2ml of 1.385 mol/L HCL (aq) at SATP? Please show your work and explain it. I really need help with this question, it's on one of my quizzes.

Answers

Answer:

[tex]V=1.61L[/tex]

Explanation:

Hello,

In this case, the undergoing chemical reaction is:

[tex]Mg+2HCl\rightarrow MgCl_2+H_2[/tex]

Next, we compute the reacting moles of each reactants:

[tex]n_{Mg}=3.712gMg*\frac{1molMg}{24.305 gMg}=0.153molMg[/tex]

[tex]n_{HCl}=1.385\frac{molHCl}{L}*0.1042L=0.144molHCl[/tex]

Then, as magnesium and hydrohloric acid are in a 1:2 molar ratio 0.153 moles of magnesium will completely react with 0.306 moles of hydrochloric acid yet we only have 0.144 moles, therefore, limiting reactant is hydrochloric acid. Thus, we compute the produced moles of hydrogen:

[tex]n_{H_2}=0.144molHCl*\frac{1molH_2}{2molHCl} =0.072molH_2[/tex]

Finally, we use the ideal gas equation with T=298K and 1atm (STP conditions) to compute the liters of hydrogen gas:

[tex]PV=nRT\\\\V=\frac{nRT}{P}=\frac{0.072mol*0.082\frac{atm*L}{mol*K}*273K}{1atm}\\ \\V=1.61L[/tex]

Best regards.

Please Help In need of chemistry help

The reaction CH4 + Br2 → CH3Br + HBr is an example of

1.Addition
2.Polymerization
3.Substitution
4.Hydrogenation

Answers

it’s an example of substitution

Triangle W Z Y is cut by bisector Z X. The lengths of sides Z W and Z Y are congruent. ZX bisects ∠WZY. If the measure of ∠YXZ is (6m – 12)°, what is the value of m?

Answers

Answer:

m = 17

Explanation:

From the question we were given that

Triangle WZY is bisected by ZX; ZW = ZY

∠YXZ = (6m – 12)°

Based on the characteristics of the triangle, we see that triangle WYZ is an isosceles triangle (that is, triangle WXZ is equal to triangle YXZ)

<YXZ = <WXZ = 90°

Using ∠YXZ  = (6m – 12)°

We have:

(6m – 12)° =  90°

6m = 90 + 12 ⇒ 6m = 102

m = 102 ÷ 6 = 17

m = 17

We therefore see that m is equal to 17

Answer:

B: 17

Explanation:

Determine the boiling point of a 3.70 m solution of phenol in benzene. Benzene has a boiling point of 80.1°C and a boiling point elevation constant of 2.53°C•kg/mol.

Answers

Answer: The boiling point of a 3.70 m solution of phenol in benzene is [tex]89.5^0C[/tex]

Explanation:

Elevation in boiling point:

[tex]\Delta T_b=i\times k_b\times m[/tex]

where,

[tex]\Delta T_b[/tex] = change in boiling point

i= vant hoff factor = 1 (for benzene which is a non electrolyte )

[tex]k_b[/tex] = boiling point constant = [tex]2.53^0C/kgmol[/tex]

m = molality = 3.70

[tex]T_{solution}-T_{solvent}=i\times k_b\times m[/tex]

[tex]T_{solution}-80.1^0C=1\times 2.53\times 3.70[/tex]

[tex]T_{solution}=89.5^0C[/tex]

Thus  the boiling point of a 3.70 m solution of phenol in benzene is [tex]89.5^0C[/tex]

Answer:

First Question:

C. ΔTb = Kbm

Second Question:

C. 9.36° C

Third Question:

89.5

Explanation:

Got it right.

what is the best way to make a supersaturated solution?
A. cool the solution
B. Stir the solution
C. Heat the solution
D. Evaporate the solution

Answers

To make a supersaturated solution, make a saturated solution of sugar by adding 360 grams of sugar to 100 mL of water at 80 degrees Celsius. When the water cools back down to 25 degrees, that 360 grams of sugar will still be dissolved even though the water should only dissolve 210 grams of sugar.

C.heat the solution

Se construye una pila galvánica con una barra de cobre sumergida en una disolución 1M de cationes Fe+2 y una barra de plata sumergida en una disolución 1M de da cationes Ag+ , Calcular el potencial estándar de la celda teniendo en cuenta que a 25°C: Cu+2/Cu = -0.34V Ag+/Ag = 0.80V

Answers

Answer:

El potencial celular estándar, [tex]E_{cell}[/tex] is +0.46 V

Explanation:

Las reacciones de media célula son;

Media reacción del ánodo Cu²⁺ + 2e⁻ ↔ Cu, E ° = 0.34 V

Media reacción catódica 2Ag + 2e⁻ ⁻ 2Ag, E ° = 0.80 V

Sin embargo tenemos para hierro Fe²⁺ + 2e⁻ ↔ Fe, E ° -0.44 V

y Fe³⁺ + e⁻ ↔ Fe²⁺, E ° = 0.77 V

 que es más alta que la del cobre presente, por lo tanto, el cobre se oxidará en el ánodo

Por lo tanto, en el ánodo, tendremos

Cu → Cu²⁺ + 2e⁻ (E ° = -0.34 V)

En el cátodo

2Ag + 2e⁻ → 2Ag (E ° = 0.80 V)

[tex]E_{cell} = E_c + E_a = -0.34 + 0.8 = +0.46 \, V[/tex]

El potencial celular estándar, [tex]E_{cell}[/tex] = +0.46 V

This is how fluorine appears in the periodic table. A green box has F at the center and 9 above. Below it says fluorine and below that 19.00. A blue arrow points to 9. What information does "9” give about an atom of fluorine? Select three options. the atomic number the atomic mass the number of protons the number of electrons the number of neutrons

Answers

1. Atomic weight of fluorine

2. Number of proton and neutrons found in the nucleus of the element

3. And every number uniquely identifies each of the the elements

what is the difference between basis and basic​

Answers

Answer:

Basis and basic​ are two different words.

In English, Basis is used as a noun while basic is used as an adjective. Basis term refers as the base or starting point of any discussion.

For example: Bread is a basic ingredient of cake.

                      On the basis of Mendel's hypothesis.

In chemistry, Basis set is used as a set of functions that represent the electronic wave function in the density-functional theory which forms an  algebraic equations that can be easily implemented on a computer.

While Basic term is used for substances that can accept a hydrogen ion (H+) from another substance and have pH above 7. such as sodium.

So, It is not important that both the terms, basis and basic change their English meaning if used in chemistry, they both can be used with English meaning in chemistry as well. Bases and basic,​ both the terms can be used as either English or Chemistry without affecting the meaning.


3. How much power is required to pull a sled if you use
60j of work in secound?

Answers

Answer:

The answer is 60W

Power = Work done/ time

time = 1 second

Work done = 60J

Power = 60/1

= 60W

Hope this helps.

Select all statements that are true for Sn1 reactions. (a) Formation of the carbocation is the rate-determining step (RDS) (b) The reaction rate depends upon the concentration of both the nucleophile and the electrophile (c) Reactions at chiral carbons proceed with inversion of stereochemistry (d) None of these statements are true for Sn1 reactions (e) Carbocation rearrangements are never observed

Answers

Answer:

(a) Formation of the carbocation is the rate-determining step (RDS)

(c) Reactions at chiral carbons proceed with inversion of stereochemistry

Explanation:

SN1 reactions arenucleophilic substitution reactions in which the rate determining step is unimolecular.

The formation of a carbocation is the rate determining step. This depends on the electrophilicity of the leaving group. Thus the SN1 reaction mechanisms is dependent on the electrophile and not the nucleophile.

Polar and acidic solvents which can assist in the formation of the carbocation speeds up the rate determining step.

If the formation of carbocation occurs at a chiral center, both retention and inversion of stereochemistry are likely to occur.

Therefore, the correct options are A and C.

Elements that form ionic bonds generally have how many valence electrons?

Answers

Answer:

they should have a number that can completely transfer and fill the other atom

Explanation:

example:

sodium(2.8.1)and Chlorine(2.8.7)the sodium will give chlorine the 1 valence electrobo so they both become stable(2.8)±and(2.8.8)–

magnesium(2.8.2)and oxygen(2.6)same way as above to abtain mg(2.8)±²and oxygen(2.8)–²

Am I correct? Because I’m kinda in between answers

Answers

Answer:

yh you are correct. the pattern is correct! :)

Answer:

Yep! :)

Explanation:

In which kingdom do all organisms have cells that lack a cell wall?
fungsi
plants
animals
bacteria

Answers

Answer:

The answer is animals

Explanation:

Plants and fungi have a cell wall, and although most bacteria lack a cell wall, the question is asking in which kingdom do ALL organisms lack a cell wall. Hope this helps.

Answer:Bacteria

Explanation:

How do you solve this

Answers

Answer:

23.6°C

Explanation:

Step 1:

Data obtained from the question. This include the following:

Mass = 0.125kg = 0.125 x 1000 = 125g

Initial temperature (T1) = 22°C

Heat (Q) generated in 4.5mins = 835J

Specific heat capacity (C) of water = 4.184J/g°C

Change in temperature (ΔT) =?

Final temperature (T2) =?

Step 2:

Determination of the change in temperature, ΔT of water.

This can be obtained as shown below:

Q = MCΔT

835 = 125 x 4.184 x ΔT

Divide both side by 125 x 4.184

ΔT = 835 / (125 x 4.184)

ΔT = 1.6°C

Therefore, the change in temperature, ΔT is 1.6°C

Step 3:

Determination of the final temperature of water.

This can be obtained as follow:

Initial temperature (T1) = 22°C

Change in temperature (ΔT) = 1.6°C

Final temperature (T2) =?

Change in temperature (ΔT) = Initial temperature – Final temperature

ΔT = T2 – T1

1.6 = T2 – 22

Collect like terms

T2 = 1.6 + 22

T2 = 23.6°C

Therefore, the final temperature of the water is 23.6°C.

A balloon has a volume of 10,500 liters, and the temperature is 15°C. If the temperature were -25°C, what would the volume of the balloon be?

12,194 L
9,042 L

Answers

12,194 L is the answer!

Explanation:

Water has the maximum density at the temperature of 4°Celsius. So, it expands at temperatures higher or lower than 4°C, knowing that at the temperature of -25°C the water can't have a lower volume than the one at 15°C.

Answer:

12, 194 L

That's your answer!!!

Which of the following is true about the principle of the conservation of mass? *
1 point
d. The mass of the products is never equal to the mass of the reactants.
e. The mass of the products is less than the mass of the reactants.
f. The mass of the products is equal to the mass of the reactants.
g. The mass of the products is greater than the mass of the reactants.

Answers

Answer:

F

Explanation:

"The mass of the products is equal to the mass of the reactants" is true about the principle of the conservation of mass.

So, option f is correct one.

What is the principle of conservation of mass?The principle of the conservation of mass states that mass can neither be created nor be destroyed in a chemical reaction, it only transferred from reactants to products. It means that mass of reactants is equal to mass of products.Example when wood burns the mass of shoot, ashes, and gases equal to the original mass of of charcoal and oxygen when it first react.

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This beaker contains an aqueous solution of copper II nitrate.

Write the chemical formula for the solute chemical that is dissolved):

Write the chemical formula for the solvent( liquid that does the dissolving)

Answers

Answer:

See the answer below

Explanation:

Aqueous solution of copper II nitrate contains solute of copper II nitrate dissolved in water. The equation for the reaction is as below:

[tex]Cu(NO_3)_2 (s)[/tex] + [tex]H_2O (l)[/tex] --> [tex]Cu(NO_3)_2 (aq)[/tex]

Hence, the solute chemical is copper II nitrate while the solvent is water.

Chemical formula of copper II nitrate - [tex]Cu(NO_3)_2[/tex]

Chemical formula of water - [tex]H_2O[/tex]

Consider the incomplete reaction below.

NaOH + X Right arrow. NaCH3COO + H2O

What is X in this reaction?
NH4OH
H3PO4
H2CO3
CH3COOH

Answers

A chemical  reaction involves the interaction of reactants. The substance X ,must be an acid and in this case is CH3COOH

What is a reaction?

In chemistry, a reaction is said to occur when substances interact in such a way that other new substances are formed.

Now let us look at the particular reaction; NaOH + X ----> NaCH3COO + H2O. The substance X must be an acid. Hence, the most likely susbstance is CH3COOH.

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The recommended dose of aspirin will yield approximately 100.0 micrograms/mL in the blood. How many molecules of aspirin (C9H8O4) are in a drop (0.100 mL) of blood?

Answers

Answer:

3.34x10¹⁶ molecules of aspirin are in a drop of blood

Explanation:

The recomended dose of aspirin in blood is 100.0μg/mL =

1x10⁻⁴g aspirin / mL of blood.

In a drop (0.100mL) there are:

0.100mL ₓ (1x10⁻⁴g aspirin / mL of blood) = 1x10⁻⁵g aspirin.

Molecular mass of aspirin is:

9C = 12.01g/mol ₓ 9 = 108.09g/mol

8H = 1.01g/mol ₓ 8 = 8.08g/mol

4O = 16g/mol ₓ 4 = 64g/mol

108.09 + 8.08 + 64 = 180.17g/mol

Thus, moles of aspirin in 1x10⁻⁵g are:

1x10⁻⁵g ₓ (1mol / 180.17g) = 5.55x10⁻⁸ moles of aspirin

In 1 mole, you have 6.022x10²³ molecules, thus:

5.55x10⁻⁸ moles of aspirin ₓ (6.022x10²³ molecules / 1 mole ) =

3.34x10¹⁶ molecules of aspirin are in a drop of blood

Compare the wavelength and energy of ultraviolet rays to visible light

Answers

Answer:

Visible wavelengths range from 0.0007 milimeters for red light, through orange, yellow, green, and blue, to 0.0004 milimeters for violet light.

Ultraviolet is shorter wavelengths than violet.

Hope This Helps.

A.
B.
C.
D.
what’s could be the correct answer?

Answers

The correct answer is A.

Explanation: An radar uses electromagnetic waves to attempt to discover objects far away such as air craft, ships, missiles etc.

Hope this helped :)
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