The percentage by mass of Na2CO3 in the sample is 48%.
The equation of the reaction of Na2CO3 with HCl;
Na2CO3(aq) + 2HCl(aq) ------> 2NaCl(aq) + H2O(l) + CO2(g)
Since the HCl is in excess, the excess is back titrated with NaOH as follows;
NaOH (aq) + HCl(aq) ---->NaCl(aq) + H2O(l)
Number of moles of HCl added = 0.100 M × 50/1000 L = 0.005 moles
Number of moles of NaOH added = 5.6/1000 × 0.100 M = 0.00056 moles
Since the reaction of NaOH and NaOH is 1:1, 0.00056 moles of HCl reacted with excess HCl.
Amount of HCl that reacted with Na2CO3 = 0.005 moles - 0.00056 moles = 0.0044 moles
Now;
1 mole of Na2CO3 reacts with 2 moles of HCl
x moles of Na2CO3 reacts with 0.0044 moles of HCl
x = 1 mole × 0.0044 moles / 2 moles
x = 0.0022 moles
Mass of Na2CO3 reacted = 0.0022 moles × 106 g/mol = 0.24 g
Percentage of Na2CO3 in the sample = 0.24 g/ 0.500-g × 100/1 = 48%
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The side of a cube is found to be 127.58 mm and its mass is found to be 7.3 kg. Determine the density of this cube in g/mL.
Answer:
3.5154 g/mL
Explanation:
You will need to use the equation Density = Mass/Volume. You are given mm(can be used to find volume) of a cube and kg(mass). Since your answer is in g and mL we should convert it to those sizes. First we want cm so we will divide the 127.58 mm to cm getting 12.758 cm. We want to cube it since we are finding the whole area of a cube( 12.758*12.758*12.758) which will equal 2076.58 cm^3. We know that 1 mL is equal to 1 cm^3, so we can take our 2076.58 cm^3 and label them as mL(which is what we want). Then we know that there are 1000g in 1 kg, so if we multiply the 7.3 kg, we get 7300g. Finally use the equation Density = Mass/Volume to get your answer. 7300g/2076.58mL = 3.5154 g/mL.
Hope this helps!
Explain in your own words:
i. Sublimation
ii. Condensation
iii. Melting
If the adoms dont work are they dead
Answer: no
Explanation:
Atoms are not and have never been alive so they can't be considered dead. they simply do not meet any reasonable of life, primarily because they are not complex.
How many hydrogen atoms are in 5CH3COOH?
Answer: This formula indicates that a molecule of acetic acid (Figure 2.21) contains two carbon atoms, four hydrogen atoms, and two oxygen atoms.
Explanation:
Of the following, ________ is the most volatile. Select one: C2F6 C2H6 C2I6 C2Cl6 C2Br6
Answer:
C2Br6
because bromine is a liquid volatile
According to the forces of attraction and boiling point C₂Br₆ is most volatile as its boiling point is very low.
What are forces of attraction?Forces of attraction is a force by which atoms in a molecule combine. it is basically an attractive force in nature. It can act between an ion and an atom as well.It varies for different states of matter that is solids, liquids and gases.
The forces of attraction are maximum in solids as the molecules present in solid are tightly held while it is minimum in gases as the molecules are far apart . The forces of attraction in liquids is intermediate of solids and gases.
The physical properties such as melting point, boiling point, density are all dependent on forces of attraction which exists in the substances.
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need help with this question asap :)
-20 points!..
Which is warmer -30C or -30 F?
-30°F is warmer than -30°C.
The -ve sign is used when the temperature drops down. Celsius is the greater unit. By converting, -30°F = -1.11°C (approx.) We know that, -1.11 > -30. So, -30°F (-1.11°C) is warmer than -30°C.
Formula :-
(x°C × 9/5) + 32 = y°F
_____
Hope it helps ⚜
Answer:
-30 c is warmer
Explanation:
-30 c =-22 f
-30 f=-34.444 c
List the four quantum numbers
Answer: In atoms, there are a total of four quantum numbers: the principal quantum number (n), the orbital angular momentum quantum number (l), the magnetic quantum number (ml), and the electron spin quantum number (ms).
Answer:
(n)
(i)
(mı)
(ms) s is suppose to be smaller than the m
Explanation:
the principal quantum number (n)
the orbital angular momentum quantum number (I)
the magnetic quantum number (ml)
the electronic spin quantum number (ms)
what is the name of the compound N2O5
Answer:
Dinitrogen pentoxide also known as Nitrogen pentoxide or nitric anhydride (these are all the same thing just different names people call them)
calculate the mass of 1 molecule of water and 100 molecules of glucose
Explanation:
Mass of one atom of water = Mass of 1 mole / Avogadro's number
Mass of one atom of water = 18g/mol / 6.022×10²³molecules
Mass of one atom of water = 2.989 × 10^-23 g
Mass of glucose = 180(one molecule)
Mass of 100 molecules of glucose = 180×100 =18000
What is the total pressure exerted by a mixture containing two gases if the partial pressure of one gas is 70 kPa and the partial pressure of the other gas is 30 kPa?
Answer:
The total pressure of a mixture of gases can be defined as the sum of the pressures of each individual gas: Ptotal=P1+P2+… +Pn. + P n . The partial pressure of an individual gas is equal to the total pressure multiplied by the mole fraction of that gas.
Explanation:
hope this helps have a wonderfull day!
which planet is closests to the moon
Answer:
Earth
Explanation:
Answer:
Earth
Explanation:
Hope this helps! Pls give brainliest! Also, please sub to Kgirl633 on yt.
What would happen if hydrogen chloride gas is bubbled through a solution of lead (II) nitrate? Explain
A white precipitate of silver chloride will be formed when Hydrogen chloride gas is passed through silver nitrate.
A white precipitate of silver chloride will be formed when Hydrogen chloride gas is passed through silver nitrate.2HCl+2AgNO³
→2AgCl+2HNO³
The reaction between AgCl and NH4OH will result in the products of Ag(NH3) 2+and Cl - ions .
AgCl+2NH 4OH→Ag(NH3) ²Cl+HH²O
[H+]=1×10−13 M pH=
what is this answeer
Answer:
Take the -logarithm of the concentration of hydrogen ions that are in the solution:
pH=−log(1×10−8M)=8.❤
An unknown solution contains several chemical substances. By following a series of steps in a procedure, each of these substances can be isolated. Which of the following methods would be most appropriate for showing the steps needed to separate the substances?
A. Draw a diagram of apparatus used.
B. Create a flowchart of the various steps.
C. Build a model of the various atomic structures.
D. Construct a graph showing the times needed for each step.
Answer:
Create a flowchart of the various steps.
Explanation:
Answer:
A.
Explanation:
have a nice day^^ good morning
How do molecules work?
A molecule is essentially created by a collection of atoms linked by a network of bonds.
What is the pressure of a 1.0 L flask containing 0.12 g of He at 25°C? (R= 0.0821 L atm/mol K)
Answer:
The pressure of the flask is 0.73 atm.
Explanation:
To solve this question, we should use the ideal gas law: PV=nRT, where P represents the pressure (in atm in this case), V represents the volume (in L), n represents the number of moles of gas, R is the ideal gas constant, and T represents the temperature (in K).
Before we can plug our values into the equation, we must convert so that our units cancel out. First, we should convert our temperature from degrees Celsius to degrees K.
25°C + 273.15 = 298.15K
Next, we should convert the 0.12 g He to moles using the molar mass of He.
0.12 g He * (1 mole He/4.003 g He) = 0.029978 mol He
Now, we can plug in the values into the equation and solve for the pressure.
PV = nRT
P = (nRT)/V
P = (0.029978 mol He * 0.0821 L*atm/mol*K * 298.15 K)/(1.0 L)
P = 0.73 atm
Therefore, the correct answer is 0.73 atm.
Hope this helps!
A solution is made by combining 15.0 g of potassium chloride with 100 g water at room temperature. What is the concentration of this solution
Answer:
Freezing point depression=2×1.027⋅mol⋅kg−1×1.86⋅K⋅kg⋅mol−1=3.82⋅K .. And so the fusion point of the solution will be −3.8 ∘C .
What is the molarity of aqueous lithium bromide if 25.0 mL of LiBr reacts with 10.0 mL of 0.250 M Pb(NO 3) 2
The molarity of aqueous lithium bromide, LiBr solution is 0.2 M
We'll begin by calculating the number of mole of Pb(NO₃)₂ in the solution.
Volume = 10 mL = 10 / 1000 = 0.01 L Molarity of Pb(NO₃)₂ = 0.250 MMole of Pb(NO₃)₂ =?Mole = Molarity x Volume
Mole of Pb(NO₃)₂ = 0.25 × 0.01
Mole of Pb(NO₃)₂ = 0.0025 mole
Next, we shall determine the mole of LiBr required to react with 0.0025 mole of Pb(NO₃)₂
Pb(NO₃)₂ + 2LiBr —> PbBr₂ + 2LiNO₃
From the balanced equation above,
1 mole of Pb(NO₃)₂ reacted with 2 mole of LiBr.
Therefore,
0.0025 mole of Pb(NO₃)₂ will react with = 2 × 0.0025 = 0.005 mole of LiBr
Finally, we shall determine the molarity of the LiBr solution
Mole = 0.005 mole Volume = 25 mL = 25 / 1000 = 0.025 L Molarity of LiBr =?Molarity = mole / Volume
Molarity of LiBr = 0.005 / 0.025
Molarity of LiBr = 0.2 M
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what is wrong with the statement? "because there are no common factors in the molecular formula, k2co3 is also the empirical formula of potassium carbonate"
The empirical formula is the same as the molecular formula because the ratio of atoms in the compound correspond to the number of atoms of each element in the compound.
The empirical formula of a compound shows the ratio of atoms of each element in the compound while the molecular formula shows the number of atoms of each element in the compound.
For the compound, K2CO3, the empirical formula is the same as the molecular formula because the ratio of atoms in the compound correspond to the number of atoms of each element in the compound. It has nothing to do with common factors.
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how many molecules are in 2.50 moles of co2
Answer:
[tex]1.51 \times 1024 \: \: molecules[/tex]
Explanation:
There are 1.51 x 1024 molecules of carbon dioxide in 2.50 moles of carbon dioxide.
What is epoxy?
....................
Answer:
1. any class of adhesives, plastics, or other materials that are polymers of epoxies.
2. something like glue or resin
Explanation:
that's the dictionary definition of epoxy.
grtdggddgdggrsggrgrgd
Answer:
wut??
Explanation:
What is the momentum of a car if its mass 200kg and moving with a speed of 3m/s?
600 kg·m/s
Given:Mass = 200 kg
Velocity = 3 m/s
Power = Mass * Velocity = 200 kg * 3 m/s = 600 kg·m/s
help pls very simple
When 2.0 mol of methanol is dissolved in 45 grams of water, what is the mole fraction of methanol
The mole fraction of methanol in the mixture is 0.444
We'll begin by calculating the number of mole of water.
Mass of water = 45 gMolar mass of water = 18 g/molMole of water =?Mole = mass / molar mass
Mole of water = 45 / 18
Mole of water = 2.5 moles
Finally, we shall determine the mole fraction of methanol.
Mole of water = 2.5 molesMole of methanol = 2 molesTotal mole = 2 + 2.5 = 4.5 molesMole fraction of methanol =?
Mole fraction = mole / total mole
Mole fraction of methanol = 2 / 4.5
Mole fraction of methanol = 0.444
Thus, the mole fraction of methanol is 0.444
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Name of equipments that uses in crude oil distillation?
Explanation:
Crude oil distillation is a complex and capital-intensive process in petroleum refining. The crude oil distillation unit comprises distillation columns, pump-around loops, side strip.pers and a heat recovery system, known as the preheat train.
describe the components of a molecule whose atoms are joined by covalent bonds.
Answer:
nonmetal
Explanation:
In a covalent bond, the atoms bond by sharing electrons. Covalent bonds usually occur between nonmetals. For example, in water (H2O) each hydrogen (H) and oxygen (O) share a pair of electrons to make a molecule of two hydrogen atoms single bonded to a single oxygen atom.
Which type of rock is formed when rocks are melted deep in the Earth and cool to form new rocks?
A. Igneous
B. Metamorphic
C. Sandstone
D. Sedimentary
Answer:
igneous
Explanation:
key word: melt, cool. igneous rocks are when lava is melted then cooled off, then becoming a igneous rock.
Can someone label these PLEASE !!! HELPPPPPP! DUE TODAYY
Answer:
1. melting
2boiling
3. freezing
4. condesation
Explanation: