A mole equals 6.02 x 10^23 . Answer these questions below.

1. How many ants are in 1.25 moles of ants?

2. How many moles of pencils are in 4.92 * 10^26 pencils?

3. How many molecules are in 0.26 moles of molecules?

4. How many moles of molecules are in 3.46 * 10^19 molecules?

5. 5.3 * 10^20 atoms are equal to how many moles of atoms?

6. 0.11 moles of atoms are equal to how many atoms?

Answer:  

1) Endothermic.  

2) [tex]Q_{rxn}=4435.04J[/tex]  

3) [tex]\Delta _rH=15.8kJ/mol[/tex]

Explanation:  

Hello there!  

1) In this case, for these calorimetry problems, we can realize that since the temperature decreases the reaction is endothermic because it is absorbing heat from the solution, that is why the temperature goes from 22.00 °C to 16.0°C.  

2) Now, for the total heat released by the reaction, we first need to assume that all of it is released by the solution since it is possible to assume that the calorimeter is perfectly isolated. In such a way, it is also valid to assume that the specific heat of the solution is 4.184 J/(g°C) as it is mostly water, therefore, the heat released by the reaction is:

[tex]Q_{rxn}=-(15.0g+250.0g)*4.184\frac{J}{g\°C}(16.0-20.0)\°C\\\\ Q_{rxn}=4435.04J[/tex]    

3) Finally, since the enthalpy of reaction is calculated by dividing the heat released by the reaction over the moles of the solute, in this case NH4Cl, we proceed as follows:

[tex]\Delta _rH=\frac{ Q_{rxn}}{n}\\\\\Delta _rH= \frac{ 4435.04J}{15.0g*\frac{1mol}{53.49g} } *\frac{1kJ}{1000J} \\\\\Delta _rH=15.8kJ/mol[/tex]

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Answer:

cerium (iii) sulfate is less soluble

Answer:

cerium sulphate is less solube when the temperature increase

Answer:

N2O5

Explanation:

1. Convert to moles

24.5g N * 1mol/14g = 1.75

70.0g * 1mol/16g = 4.375

2. Divide each value by the smallest

1.75/1.75 = 1

4.375/1.75 = 2.5

3. Multiply each by a whole number so that they are both whole numbers

1*2 = 2

2.5*2 = 5

4. These are moles of elements present in the compound

Answer: N2O5

Question: You decompose a compound containing nitrogen and oxygen in the laboratory and produce 24.5 g of nitrogen and 70.0 g of oxygen. Calculate the empirical formula of the compound.

Answer:

The Periodic Table can be divided into s, d, p, and f sublevel blocks. For elements in the s sublevel block, all valence electrons are found in s orbitals. For elements in the p sublevel block, the highest energy valence electrons are found in p orbitals.

Explanation:

Answer:

3.7 x 10²¹ O₂ molecules

Explanation:

2KClO₃ => 2KCl + 3O₂

given 0.500g KClO₃ => 0.500g/122.55g/mol = 0.0041 mole KClO₃

0.0041 mole KClO₃ => 3/2(0.0041) mole O₂ = 0.0061 mole O₂

0.0061 mole O₂ = 0.0061 mole O₂ x 6.02 x 10²³ molecules O₂/mole O₂

= 3.7 x 10²¹ molecules O₂

Answer:

Two of them are solids, one is liquid. Two of them are edible, one is not. One is a mixture, and two are not.

Explanation:

this is true, wind energy is a renewable natural resource c:

The methods of fossil formation in dry areas due to a lack of moisture is mummification. The correct option is a.

Mummification is the process of deliberately drying or embalming flesh to preserve the body after death.

This typically entailed removing moisture from a deceased body and desiccating the flesh and organs with chemicals or natural preservatives such as resin.

Mummification served the purpose of keeping the body intact so that it could be transported to a spiritual afterlife.

The body was stripped, positioned on a slanted table, and washed in natron solution (a naturally occurring salt used both as soap and a preservative).

The brain was extracted from the skull through a hole in the ethmoid bone (the bone separating the nasal cavity from the skull cavity).

Thus, the correct option is A.

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Answer:

C the temperature will increase.

Answer:

[tex]\boxed {\boxed {\sf 2.76 \ mol}}[/tex]

Explanation:

Molarity is found by dividing the moles of solute by liters of solution.

[tex]molarity = \frac {moles}{liters}[/tex]

We know the molarity is 1.2 M (mol\liter) and there are 2.3 liters of solution. Substitute the known values into the formula.

[tex]1.2 \ mol/liter= \frac {x}{2.3 \ liters}[/tex]

Since we are solving for x, we must isolate the variable. It is being divided by 2.3 and the inverse of division is multiplication. Multiply both sides by 2.3 liters.

[tex]2.3 \ liters *1.2 \ mol/liter= \frac {x}{2.3 \ liters}* 2.3 \ liters\\2.3 *1.2 \ mol= x\\2.76 \ mol =x[/tex]

In a solution with a molarity of 1.2 and 2.3 liters of solution, there are 2.76 moles.

Answer:

E  3.0 x 10² mL.

Explanation:

Hello there!

In this case, according to the formula for the calculation of the mass-volume percent:

[tex]\% m/V=\frac{m_{solute}}{V_{solution}}*100\%[/tex]

Whereas it is necessary to know the mass of the solute and the volume of the solution. Thus, given the mass of NaOH as the solute, the volume of the solution would be:

[tex]V_{solution}=\frac{m_{solute}}{\% m/V}*100\%[/tex]

Then, by plugging in we obtain:

[tex]V_{solution}=\frac{75g}{25\%}*100\%\\\\V_{solution}=3.0x10^2mL[/tex]

Thus, the answer is E  3.0 x 10² mL.

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Answer:

An area with the same climate, landscape, plants, and animals.

Answer:

B. Salt water has too few water molecules and too many salt molecules

Explanation:

Seawater is toxic to humans because your body is unable to get rid of the salt that comes from seawater. Your body normally gets rid of excess salt by having the kidneys produce urine, but it needs freshwater to dilute the salt in your body for the kidneys to work properly.

Answer:

1500ml

Explanation:

molarity=3.65⋅g36.5⋅g⋅mol−1500⋅mL×10−3⋅L⋅mL−1=0.200⋅mol⋅L−1

Answer:

D is the answer i think

Explanation:

The answer to your question is true

The statement "The scientific method is a rigid process" is false.

The method by which scientist search for solutions and answers to their problem and question with the help of procedure is called scientific method.

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Answer:

Phenol is more acidic than alcohol due to resonance stabilization of the phenoxide ion.

Answer:

No Just because a trait is dominant does not mean that it is present in the population

Explanation:

Answer:

The three main kinds of intermolecular interactions are dipole-dipole interactions, London dispersion forces, and hydrogen bonds

Explanation:

Answer:

All scorpions fluoresce under ultraviolet light, such as an electric black light or natural moonlight. The blue-green glow comes from a substance found in the hyaline layer, a very thin but super tough coating in a part of the scorpion's exoskeleton called the cuticle

Explanation:

Answer:

All scorpions fluoresce under ultraviolet light, such as an electric black light or natural moonlight. Much like many other creepy, crawly insects, scorpions like hiding in dark places. ... If you're worried that you may have a scorpion problem, you can use a black light to search for them at night. When a black light hits a scorpion, the proteins on its exoskeleton create a bright neon blue hue.Scorpions do not like heat and bright light. They lose some of what little water they have to evaporation. So they use their sensitivity to UV rays to determine if it's dim enough for them to crawl out and get to business. He thinks that scorpions glow to convert the dim UV light from the moon and the stars into the colour that they see best – blue-green. This could explain why scorpion eyes are so exquisitely sensitive, to the point where they can detect the faint glow of starlight against the background of the night sky.Given the high densities of scorpions in some areas, their importance in ecological food webs, particularly with respect to helping control insect populations, is considerable. Many are sensitive to environmental degradation and are considered equilibrium species. Ecology: Scorpions are primarily nocturnal.Scorpions are preyed upon by large centipedes, tarantulas, lizards, birds (especially owls), and mammals such as bats, shrews, and grasshopper mice.

Explanation: I added a little more info about them please give me brainliest

The concept Charles's law is used here to determine the new volume. At the condition of constant pressure the new volume of the balloon is 459.54 mL.

At constant pressure, the volume of a given mass of gas is directly proportional to the temperature on Kelvin scale. Mathematically, the law can be expressed as follows:

V = constant × Temperature

V / T = Constant

V = Volume

T = Temperature

The Charles's law also explained that at -273°C, the volume of all the gases will become zero. This temperature is defined as the absolute zero.

For two different gases with volumes V₁ and V₂ and temperatures T₁ and T₂ is represented as:

V₁ / T₁ = V₂ / T₂

V₂ = V₁T₂ / T₁

222 × 62.1 / 30.0 = 459.54 mL

Thus the new volume of balloon is 459.54 mL.

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Answer:  

Molarity=moles of solute/ L of solution

Molality = moles of solute/ kg of solvent

Solute= what is being dissolved

Solvent= what is doing the dissolving

Solution= both together

Explanation:

Example's:

#1.  For number one you use the Molarity formula.  M= moles of solute/ L of solution.

To find moles of Mg(NO3)2 you divide 95g by its molar mass which is 148.33g so 95/148.33=.6405 moles of Mg(NO3)2.  Then plug in what you have.  .38M= .6405 moles Mg(NO3)2 / X.  Then solve for X using algebra.  .6405/.38= 1.686 L of solution.  (Volume).

Final Answer: 1.686 L

#2.  For number 2 you use the Molality formula.  m= moles of solute/ kg of solvent.

First you have to find moles of glucose by taking 267g and dividing it by its molar mass which is 180.56g.               267g/180.56g= 1.532 moles of glucose.  Then you have to change L to kg.  The easiest way to do this is to look at the density and see that for every 1 ml there is 1 gram.  So to take Liters to ml you multiply 1.59 by 1000 and get 1590 ml.  So that means you have 1590 grams. then you divide 1590grams by 1000 to get 1.59 Kg of slovent.  Then plug in your information into the formula.      molality= 1.532 moles of glucose / 1.59 Kg of solvent= .964 molality.

Final answer: .964 mol/Kg

#3.  m= moles of solute / Kg of solvent.  0.445 mol solute / 2.07 Kg solvent= .215 Molality

Final Answer: .215 mol/Kg

#4. m= moles of solute / Kg of solvent.  take 13.5g and divide it by ethylene glycols molar mass which is 62.068 g.  13.5g / 62.068g= .218 mol.  Then you take 135g of water and divide it by 1000 to get Kg.  135/1000=.135 Kg.  Then plug in your information.  m= .218mol/.135 Kg= 1.615 molality

Final Answer: 1.615 mol/Kg.

Answer:

2

Explanation:

zeros are not considered sig figs

Answer: Yes, light can bend around corners. In fact, light always bends around corners to some extent.

Explanation:This is a basic property of light and all other waves. ... The ability of light to bend around corners is also known as "diffraction".

Answer:

The temperature of the gas is 293.15 K.

The temperature of the gas is 303.15 K.

The new pressure of the gas is 0.97 atm.

Explanation:

You need to add 273.15 to the Celsius temperature to convert from Celsius to Kelvin.

So,

20.0°C + 273.15 = 293.15 K.

30.0°C + 273.15 = 303.15 K.

We can use the following equation to calculate the new pressure:

[tex]P_2 = P_1 *\frac{T_2}{T_1}[/tex]

where:

Plugging in the values from the problem, we get:

[tex]P_2 = 1.00 atm * \frac{303.15 K }{293.15 K} = 0.97 atm[/tex]

Therefore, the new pressure of the gas is 0.97 atm.

Answer:

We can simply refer to the cation in the ionic compound as magnesium. Phosphorus, Pstart text, P, end text, is a group 15 element and therefore forms 3- anions.

Explanation:

Because it is an anion, we add the suffix -ide to its name to get phosphide as the name of the ion.

Answer:

good luck tho

Explanation:

Answer: true

Explanation: