Moles to mass
HELP PLEASE
15 pts

Answer:hop this helps

Explanation:

After heating the crucible, cooling, and weighing the sample as 0.739 g, the students should have heated the crucible again and then reweigh the sample until a constant weight is obtained.

The sample being heated, CaCl2 2 H2O, contains water of hydration.

In order to arrive at an anhydrous sample of the salt, all the water molecules must be completely evaporated off by heating.

To do so, the sample should have been heated to constant weight by repeated heating and weighing until there is no longer a change in the weight of the sample.

More on drying samples can be found here: https://brainly.com/question/21529281

Taking into account the definition of a system of linear equations and molar mass, the molar masses of elements A and B are 26.778 [tex]\frac{g}{mole}[/tex] and 17.998[tex]\frac{g}{mole}[/tex] respectively.

A system of linear equations is a set of two or more equations of the first degree, in which two or more unknowns are related.

Solving a system of equations consists of finding the value of each unknown so that all the equations of the system are satisfied. That is to say, the values ​​of the unknowns must be sought, with which when replacing, they must give the solution proposed in both equations.

The molar mass of substance is a property defined as its mass per unit quantity of substance, in other words, molar mass is the amount of mass that a substance contains in one mole.

The molar mass of a compound (also called Mass or Molecular Weight) is the sum of the molar mass of the elements that form it (whose value is found in the periodic table) multiplied by the number of times they appear in the compound.

Being the molar masses of the compounds:

and considering the definition of molar mass of a compound, the system of equations to be solved is

[tex]\left \{ {{3mA + mB=98.33\frac{g}{mole} } \atop {mA + 2mB=62.77\frac{g}{mole} }} \right.[/tex]

where mA and mB are the molar masses of elements A and B respectively.

There are several methods to solve a system of equations, it is decided to solve it using the substitution method, which consists of clearing one of the two variables in one of the equations of the system and substituting its value in the other equation.

Isolating the variable mB from the first equation:

mB= 98.33 [tex]\frac{g}{mole}[/tex] - 3mA

and substituting in the second equation, you get:

mA + 2× (98.33 [tex]\frac{g}{mole}[/tex] - 3mA)=62.77[tex]\frac{g}{mole}[/tex]

Solving:

mA + 2× 98.33 [tex]\frac{g}{mole}[/tex] - 2×3mA=62.77[tex]\frac{g}{mole}[/tex]

mA + 196.66 [tex]\frac{g}{mole}[/tex] - 6mA=62.77[tex]\frac{g}{mole}[/tex]

mA - 6mA=62.77[tex]\frac{g}{mole}[/tex] - 196.66 [tex]\frac{g}{mole}[/tex]

(-5)mA= - 133.89 [tex]\frac{g}{mole}[/tex]

mA= (- 133.89 [tex]\frac{g}{mole}[/tex] )÷ (-5)

mA= 26.778 [tex]\frac{g}{mole}[/tex]

Remember that mB= 98.33 [tex]\frac{g}{mole}[/tex] - 3mA, replacing the value of mA:

mB= 98.33 [tex]\frac{g}{mole}[/tex] - 3×(26.778 [tex]\frac{g}{mole}[/tex])

mB= 80.334 [tex]\frac{g}{mole}[/tex]

mB= 17.998 [tex]\frac{g}{mole}[/tex]

Finally, the molar masses of elements A and B are 26.778 [tex]\frac{g}{mole}[/tex] and 17.998[tex]\frac{g}{mole}[/tex] respectively.

Learn more about

system of equations:

brainly.com/question/14323743

brainly.com/question/1365672

brainly.com/question/20533585

brainly.com/question/20379472

molar mass:

brainly.com/question/5216907

brainly.com/question/11209783

brainly.com/question/7132033

brainly.com/question/17249726

Answer:

The answer is D) 51.2%

Explanation:

5.12g of 10.00g of the substance is water:

percentage of water= 5.12 x 10.00 =51.2%

Answer:

b

Explanation:

Answer:

yes it does look correct. good job.

Post- lab the percent sugar 46%, and the molar mass of sugar is 342 g/mol,  the mass of dissolved sugar to moles is 0.00497 moles of sugar to molecules of sugar is  2.992934 × 10^21 molecules, assuming the sticks of gum were exactly the same mass and sugar content, the moles would double  0.00994 moles.

moles is the unit of the molecule and it is defined as the number of molecules participating in a chemical reaction and value of one mole is equal to Avogadro constant that is 2.303 × 10²³

Sugar percentage = mass of sugar / mass of gum × 100  = 1.7 / 3.7 × 100 =  45.94 (46%)

Molar mass of sugar = C12H22O11 = C=12×12=144 + H=1×22=22  + O=16×11=176 = 342 g/mol  

Mass of dissolved sugar to moles = 1.7 g ÷ 342 g/mol = 0.00497 moles

The moles of sugar to molecules of sugar = 0.00497 mole × 6.022 × 10^23 = 2.992934 × 10^21 moleculesIn the given theory using four pieces of gum will exactly be the same to the mass of sugar.2 ÷ 342 g/mol × 1.7 = 0.00994 moles

The mass of the saliva alter the experimental data because it is not possible to remove all the saliva from the surface as it gets stick to the paper which changes the amount of sugar.

Therefore, the percent sugar 46%, and the molar mass of sugar is 342 g/mol, the mass of dissolved sugar to moles is 0.00497 moles of sugar to molecules of sugar is  2.992934 × 10^21 molecules, assuming the sticks of gum were exactly the same mass and sugar content, the moles would double  0.00994 moles.

Learn more about moles , here:

https://brainly.com/question/13611430

#SPJ2                            

Answer:

c. chemical and physical

The stability of atoms whose subshells are half-filled with electrons is due to equilibrium and symmetry.

The stability of an atom of an element depends on the number of electrons in its valence shell.

Atoms whose valence shells are completely filled are particularly stable atoms.

Similarly, subshells half-filled with electrons are particularly stable.

The stability of subshells half-filled with electrons can be explained based on equilibrium and symmetry.

A half-filled subshell distributes the energy of the electrons evenly and symmetrically such that the atom attians stability.

Therefore, stability of subshells half-filled with electrons is due to equilibrium and symmetry.

Learn more about electrons at: https://brainly.com/question/21977349

Based on the drug dosage provided, cheapest drug for treating headache is Tylenol at a cost of 3.34×10^-23 $/molecule.

A drug dosage is the amount of a drug taken by an individual that produces a therapeutic effect.

The dosage of each drug is given below:

Amount of each drug required by individual is as follows:

Acetaminophen = 240 mg/35 × 130 = 891.43 mg

Ibuprofen = 113 mg/25 × 130= 587.6 mg

Paracetamol = 102mg/15 × 130 = 884 mg

Cost of drug per mg of active ingredient is as follows;

Excedrin =  $15.51/(200 * 250 mg) = 0.0003102 $/mg

Advil = $15/(300 * 200mg) = 0.00025 $/mg

Tylenol = $14.97/(500mg × 225) = 0.000133 $/mg

Cost of each drug for treatment of headache:

Excedrin = 0.0003102 $/mg × 891.43 mg = $0.278

Advil = 0.00025 $/mg × 587.6 mg = $0.147

Tylenol = 0.000133 $/mg × 884 mg = $0.118

Thus, Tylenol is the cheapest drug for treating headache.

Molar mass of paracetamol = 151 g = 151000 g

There are 6.02 × 10^23 molecules in 151000 mg of paracetamol.

Cost per molecule = 0.000133 $/mg × (15000 mg/6.02 × 10^23)

Cost per molecule = 3.34 × 10^-23 $/molecule

Therefore, the cheapest drug for treating headache is Tylenol at a cost of 3.34×10^-23 $/molecule.

Learn more about drug dosage at: https://brainly.com/question/24793154

Answer:

When both liquid molecules are polar then they can attract one another - which leads to mixing (miscibility).

When the molecular liquid is nonpolar, then the water molecules attract only one another while ignoring the nonpolar liquid. the result is that the two liquids are immiscible.

Explanation:

I hope it helps mark me brainliest^^

Answer:

They lack lack inter-molecular forces to disolve in the polar liquids.

Explanation:

Miscibility is the property of two substances to mix in all proportions (that is, to fully dissolve in each other at any concentration). Polar molecules like water will mix well with some other polar molecules but things like oil which are non polar do not mix well with polar molecules. This is because the oil and water lack inter-molecular forces to keep them mixed.

Answer: Look up a video, and they will tell/show you.

Answer:

Rows on the periodic table represents a period, which is the number of energy levels or rings. It is the last shell which valence electrons are on.

For example the first row waas Hydrogen and Helium which each have one  energy level.

The esecond row has Carbon and Oxygen which has two energy level.

The third row has Sodium which has three energy levels and so on.

Answer:

i think b is the answer hope this helps:))

Answer:

i believe 223

Explanation:

T2 + 500k = 223 C*

The amount of heat energy needed to cause the rise in temperature of the water initially at 4 degreess Celsius is 13,794 J.

The quantity of heat required to raise the temperature of the water is calculated as follows;

Q = mcΔθ

where;

Q = 100 x 4.18 x (37 - 4)

Q = 13,794 J

Thus, the amount of heat energy needed to cause the rise in temperature of the water initially at 4 degreess Celsius is 13,794 J.

Learn more about heat energy here: https://brainly.com/question/7541718

The molecular formular shows all the atoms in the compound. The molecular formula of the compound is C15H10O5.

The molecular formula is the formula of the compound that shows the total number of atoms in a compound.

We know that;

ΔT = K m i

ΔT = 26.4°C

K = 40.0°C kg/mol

m = ?

i = 1

26.4°C = 40.0°C kg/mol * m * 1

m = 26.4°C/40.0°C kg/mol  = 0.66 m

We know that

m = mass/molar mass ÷ mass of solvent(in Kg)

Let the molar mass be MM

m = 3.044 g/MM ÷ (18 * 10^-3 Kg)

0.66 m =  3.044 g/0.018MM

0.66 m  * 0.018MM =  3.044 g

MM = 3.044 g/0.66 m  * 0.018

MM = 256 g/mol

Now;

Mass of C =  17.80 * 10^-3/44 * 12 = 0.00485 g

Moles of C = 0.00485 g/12 g/mol = 0.0004 moles

Mass of H = 2.08 * 10^-3/18  * 2 = 0.0002 g

Moles of H =  0.0002 g/1 g/mol = 0.0002 moles

Mass of O = [7.40 * 10^-3 - (0.00485 + 0.0002)] = 0.00235 g

Moles of O = 0.00235 g/16 g/mol = 0.000147 moles

Divide through by the lowest number of moles;

C - 0.0004/0.000147  H - 0.0002/0.000147  O - 0.000147 /0.000147

C - 3   H  -  2  O -  1

The empirical formula is C3H2O

So;

[3(12) + 2(1) + 1(16)]n = 256

[36 + 2 + 16]n = 256

n = 5

Molecular formula = C15H10O5

Learn more about molecular formula: https://brainly.com/question/14425592?

Answer:

Grignard reagents are made through the addition of magnesium metal to alkyl or alkenyl halides. The halide can be Cl, Br, or I (not F). It’s slightly easier to make Grignards from the iodides and bromides, however. Note what’s happening here – the magnesium is “inserting” itself between the carbon and the halide. This halide the “X” referred to when we refer to Grignard reagents as “RMgX”.

formation-of-grignard-reagents-from-alkyl-or-alkenyl-halides

Reaction Of Grignard Reagents With Aldehydes To Give Secondary Alcohols

One of the most common uses of Grignard reagents is in their reaction with aldehydes and ketones to form alcohols. In the first step, the Grignard forms the carbon-carbon bond. This results in an alkoxide (the conjugate base of an alcohol). To form the alcohol, it’s necessary to add acid at the end of the reaction (in what’s called the “workup” step). This is shown here as “H3O+” (the “X” is just the counter-ion, a spectator here)

reaction-of-grignard-reagents-with-aldehydes-to-give-secondary-alcohols

Reaction Of Grignard Reagents With Ketones To Give Tertiary Alcohols

The reaction behaves similarly with ketones. Again, there’s nothing special about the Cl here – it all depends on how you made the Grignard in the first place.

eaction-of-grignard-reagents-with-ketones-to-give-tertiary-alcohols

Grignards Add Twice To Esters And Acid Halides

Grignard reagents will also add to esters. What makes these reactions a little more complicated is that they add twice. The net result (after addition of acid) is a tertiary alcohol. This is also the case for acid halides (acyl halides) and anhydrides. One notable exception is carboxylic acids (more on that below).

reaction-of-grignard-reagents-with-esters-to-give-tertiary-alcohols-double-addition

reaction-of-grignard-reagents-with-acid-halides-to-give-tertiary-alcohols-double-addition

Addition Of Grignard Reagents To Epoxides

Another important reaction of Grignard reagents is that they will add to epoxides to form carbon-carbon bonds. One thing to keep in mind here is that the tendency is for them to add to the less substituted end of the epoxide – that is, the less sterically hindered end. You can think of this reaction as being essentially similar to an SN2 reaction. After addition of acid, an alcohol is obtained.

reaction-of-grignard-reagents-with-epoxides-to-give-alcohols

Reaction Of Grignard Reagents With Carbon Dioxide To Give Carboxylic Acids

Grignard reagents also add to carbon dioxide (CO2) to form carboxylates, in a reaction similar to their reactions with ketones and aldehydes. The carboxylates are converted to carboxylic acids after addition of acid (such as our trusty H3O(+) ).

reaction-of-grignard-reagents-with-co2-carbon-dioxide-to-give-carboxylic-acids

Grignard Reagents Are Strong Bases – Protonation (And Deuteration)

Finally, since Grignard reagents are essentially the conjugate bases of alkanes, they’re also extremely strong bases. This means that sometimes acid-base reactions can compete with their nucleophilic addition reactions. One common situation where this crops up is when Grignard reagents are added to carboxylic acids. It’s easy to forget that carboxylic acids… are acids. This means that instead of adding to the carbonyl, they react with the proton instead and form the carboxylate salt.

reaction-of-grignard-reagents-with-acidic-hydrogens-acids-to-incorporate-h-and-deuterium

This can also be used to convert alkyl halides to alkanes. First you treat it with magnesium, and then you treat the Grignard with a strong acid. This gives you the alkane. You can also use this to introduce deuterium (D) into molecules! The first step is to make the Grignard reagent. The second is to treat that Grignard with a deuterated acid such as D2O. This gives you the deuterated alkane!

Mechanism: Addition Of Grignard Reagents To Aldehydes And Ketones

So how does it work? The key to the Grignard reagent is actually very simple. When you think about the relative electronegativities of carbon (2.5) and magnesium (1.1), the bond between carbon and magnesium is polarized toward carbon. That means that carbon is more electron rich than magnesium and is actually nucleophilic! Here’s a closer look.

mechanism-for-addition-of-grignard-reagents-to-aldehydes-or-ketones

In the reaction of Grignards with aldehydes, the carbon attacks the carbonyl carbon and performs a 1,2-addition to give an alkoxide. In the second step, acid is added to give you the alcohol.

Using the stoichiometry of the balanced chemical reaction, the mass of the Ti is 144Kg.

The term chemical reaction refers to the combination of two or more substances to yiled one or more products.

The reaction equation here is; 4Na(s) + TICI4---->Ti(s) + 4NaCl(s)

Number of moles of TiCl4 = 570  * 10^3g/190 g/mol = 3000 moles

If 1 mole TiCl4 produces 1 mole of Ti

3000 moles of TiCl4 produces 300o moles of Ti

Mass of Ti produced = 3000 moles * 48 g/mol = 144Kg

Learn more about titatnium: https://brainly.com/question/14356798

The formation of ammonia gas involves reacting hydrogen gas and nitrogen gas in a mole ratio of 3 to 1. as shown below:

Ammonia gas is formed from the reaction between nitrogen gas and hydrogen gas.

Three moles of hydrogen gas will react with 1 mole of nitrogen gas to form 2 moles of ammonia gas.

The equation of the reaction is given below as:

[tex]N_2 + 3H_2 \rightarrow 2NH_3[/tex]

Therefore, the formation of ammonia gas involves reacting hydrogen gas and nitrogen gas in a mole ratio of 3 to 1.

Learn more about ammonia gas at: https://brainly.com/question/7982628

1129.9 grams of rock salt, NaCl needs to be added to a 3.78 kg of ice, to get the temperature to drop to -19C .

Freezing point depression refers to a property of solutions where addition of a solute lowers the normal freezing point of the solvent.

The Blagden's Law given as the equation above is used to determine the freezing point depression of ice:

where;

For NaCl, i = 2

Kf for water/ice = 1.86 °C kg/mol

molalityof NaCl = (mass/molar mass

l)/kg of ice

molar mass of NaCl = 58.5

mass of ice = 3.78 kg

Let molality of NaCl = m

ΔT = 19 °C

Substituting the values:

19 = 2 x 1.86 °C kg/mol x m

m = 5.11 mol/kg

mass of NaCl = 5.11 × 3.78 × 58.5

mass of NaCl = 1129.9 g

Therefore, the mass in grams of rock salt, NaCl that needs to be added to a 3.78 kg of ice, to get the temperature to drop to -19C is 1129.9 g

Learn more about freezing point depression at: https://brainly.com/question/26525184

Answer:

A. Plants

Explanation:

Plants are producers, which make their own food. Other organisms, such as rodents, birds, and wild cats, are consumers, which receive their energy from plants or other consumers.

So

Moles of Oxygen:-

3 mol of O_2 produces 2 mol SO_2

1 mol of ao_2 produces 2/3=0.6mol So_2

1.396 mol produces 0.8376mol SO_2

Mass of SO_2

Based on the charge on the aluminium ion, 0.9 g of aluminium are deposited by 0.1 F of electricity.

Electrolysis is the decomposition of a substance known as an electrolyte when electric current is passed through it.

The mass and hence moles an electrolyte deposited when current is passed through it depends on the charge on the ion.

Aluminium ion has a charge of +3 and requires 3F of electricity to deposit 1 mole or 27 g of aluminium

0.1 F will discharge = 0.1/3 × 27 g of aluminium

mass of aluminium deposited = 0.9 g of aluminium.

Therefore, 0.9 g of aluminium are deposited by 0.1 F of electricity.

Learn more about electrolysis at: https://brainly.com/question/26050361

Answer:

A

Explanation:

it can occur between two hydrogen bonds

Answer:

B

Explanation:

A mixture in which the composition is not uniform throughout.

Same thing letter B says.

Answer:

I think it’s  aq but your choice.

Explanation:

If 4.74 g of calcium carbonate is heated, the volume of [tex]CO_2[/tex] that would be produced at STP will be 1.08 L

From the equation of the reaction:

[tex]CaCO_3 --- > CaO + CO_2[/tex]

The mole ratio of [tex]CaCO_3[/tex] and [tex]CO_2[/tex] is 1:1

Mole of 4.74 g  [tex]CaCO_3[/tex] = 4.74/100 = 0.0474 moles

Equivalent mole of [tex]CO_2[/tex] = 0.0474 moles

1 mole of gas at STP = 22.71 L

0.0474 moles  at STP = 22.71 x 0.0474 = 1.08 L

More on the volume of gas at STP can be found here: https://brainly.com/question/11676583

Answer: 1. Mineral

Explanation:

       Calcite is a "white or colorless mineral consisting of calcium carbonate" (Oxford Languages).

       By this definition, the answer to your question is option 1.

The image attached is from geology.com and is a picture of calcite.