TOPICAL ASSINMENT 2
1. If 25cm' of O.IM H,SO, solution neutralised a solution containing 1.06g anhydrous sodium carbonate in
250cm. of solution, calculate the molarity and the volume of the sodium carbonate solution used. (3mks)
The molarity = 0.04 M
The volume = 6.25 ml
Further explanationGiven
25cm³ of 0.1 M H₂SO₄
1.06g Na₂CO₃ in 250cm³ of solution
Required
the molarity and the volume of Na₂CO₃
Solution
Molarity of Na₂CO₃ :
[tex]\tt \dfrac{1.06/106~mol}{0.25~L}=0.04~M[/tex]
Reaction
H₂SO₄ + Na₂CO₃ ⇒Na₂SO₄ + H₂O + CO₂
mol H₂SO₄ = 25 x 0.1 = 0.25 mlmol= 2.5 x 10⁻⁴ moles of Na₂CO₃
The volume of solution used :
[tex]\tt V=\dfrac{n}{M}=\dfrac{2.5.10^{-4}}{0.04}=6.25.10^{-3}~L=6.25~ml[/tex]
5(a) Consider the following schemes
Petroleum
>petroleum fractions
Higher petroleum fractions 1 , petrol + x
X + Y MI >CH,CICH,CI
nX"V (CH2 - CH2 - CH2-CH2)n
(i) State the type of reaction involved in I to IV
Answer:
is number 1
Explanation:
cause i know
For the reaction C+2H 2 —->CH 4 calculate the percent yield if 98 g of methane is produced when 100. g of carbon reacts with an excess of hydrogen?
The percent yield : 73.5%
Further explanationGiven
Reaction
C+2H₂⇒CH₄
Required
The percent yield
Solution
mol of Carbon(as a limiting reactant) :
[tex]\tt \dfrac{100}{12}=8.3[/tex]
mol CH₄ based on C, and from equation mol ratio C : CH₄, so mol CH₄ = 8.3
Mass of Methane(theoretical yield) :
[tex]\tt mass=mol\times MW\\\\mass=8.3\times 16=133.3~g[/tex]
[tex]\tt \%~yield=\dfrac{actual}{theoretical}\times 100\%\\\\\%yield=\dfrac{98}{133.3}\times 100\%=73.5\%[/tex]
There is an equal number of protons and __________ in a neutral atom.
A. electrons
B. neutrons
C. protons
D. elements.
the answer is electrons
The density of H2O2 is 1.407 g/mL, and the density of O2 is 1.428 g/L. How many liters of O2 can be made from 55 mL H2O2
Explanation:
mass H2O2 = 55 mL(1.407 g/mL) = 80.85 g
molar mass H2O2 = 2(1.01 g/mol) + 2(16.00 g/mol) = 34.02 g/mol
moles H2O2 = 80.85 g/34.02 g/mol = 2.377 moles H2O2
For each mole of H2O2 you obtain 0.5 mole of O2 (see the equation).
moles O2 = 2.377 moles H2O2 (1 mole O2)/(2 moles H2O2) = 1.188 moles O2
Now, you need the temperature. If you are at STP (273 K, and 1.00 atm) then 1 mole of an ideal gas at STP has a volume of 22.4 L. Without temperature you are not really able to continue. I will assume you are at STP.
Volume O2 = 1.188 moles O2(22.4 L/mole) = 0.0530 L of O2.
which is 53 mL.
All living organisms are composed of
OA. at least three cells.
ОВ.
one or more cells.
OC. at least 100 cells.
OD. only one cell.
Answer:
OB- one or more cells
Explanation:
hope this helps :)
hey what's the value of pi till
5 digits after decimal
Answer:
Pi to 5 decimals is 3.14159-
Brainlist pls!
P.S. It's a repeating number, but you can just put a (-), so that you don't have to type the whole thing out.
Answer:
sorry raaz report mat kerna
points collect kr rehe hai
Which of the following is composed mostly of ice?
Asteroids
Gaseous planets
Comets
Meteorites
Stars
Answer: The answer is C- comets!
Explanation: Callisto is composed mainly of rock and water ice, although other ices like ammonia ice and carbon dioxide ice may be present. Water ice occurs at the surface of Callisto so it would be comets.
What is different about the atomic structure of the oxygen isotopes?
Answer:
Each isotope of oxygen contains 8 protons, but differs in the number of neutrons. An isotope number is a shorthand representation of its mass. Because protons and neutrons are roughly equal in mass, an isotope's number is equal to the sum of its protons and neutrons.
Explanation:
Isotopes are atoms of the same element that have different numbers of neutrons but the same number of protons and electrons. The difference in the number of neutrons between the various isotopes of an element means that the various isotopes have different masses.
Plastic is used to cover the copper wire in the power codes of appliances because plastic differs from copper in _________
Answer:
in copper from different plastics because appliances of codes to power day in wire copper the cover to use to plastic
Replication, Transcription, and Translation Chart
Please answer
DNA Replication:
1。Template Strand: Start with this nucleotide chain.
TACCCTTGAATAAAAAATCTCTGTTTGGTCGGTATTGTTGAAATC
2。Complementary DNA Strand: Write directly below template strand.
Transcription:
3。mRNA Strand: Write the complementary mRNA strand from the DNA template strand (#1).
Translation:
4。Anticodon: Write the anticodon sequence to match the mRNA strand (#3).
5。Protein Synthesis: Write the mRNA sequence that is complementary to the anticodons. Meaning the opposite code of the anticodons (#4).
6。Amino Acid Sequence: Create the amino acid sequence from protein synthesis using 3 letter abbreviation for amino acids (#5).
I can help with 1, 2, 3, and 4... 5 and 6, I don't understand.
Template sequence : TACCCTTGAATAAAAAATCTCTGTTTGGTCGGTATTGTTGAAATC
Complement sequence : ATGGGAACTTATTTTTTAGTGTCAAACCAGCCATAACAACTTTAG
mRNA sequence : AUGGGAACUUAUUUUUUAGAGACAAACCAGCCAUAACAACUUUAG
Anticodon sequence : AUG-GGA-ACU-UAU-UUU-UUA-GAG-ACA-AAC-CAG-CCA-UAA-CAA-CUU-UAG
(not 6) Protein synthesis : START-Gly-Thr-Tyr-Phe-Leu-Glu-Thr-Asn-Gin-Pro-Stop
Which of the following reactions would result in increased entropy?
Answer:
A option
Explanation:
Because recatants are in solid form having less enetropy and products are liquid form having more entropy
While other options reactants and products are in same phase gas phase having same entropy
The reaction that would result in increased entropy is the combustion reaction;
KNO3(s)--->K+(aq)+NO3-(aq). Option A
This is further explained below
What is a combustion reaction?Generally, a combustion reaction is simply a combustion process that occurs when a material combines with oxygen gas, producing energy as light and heat.
In conclusion, the chemical reaction KNO3(s)--->K+(aq)+NO3-(aq) is has all properties of a combustion reaction as the solid reactants gives an aq solution.
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Name the three stress forces that cause changes in Earths crust. Explain how each type of force affects rock.Identify the type of fault that each force produces. This is science i couldnt find a science thing
Answer:
Shear
Tension
Compression
Explanation:
The 3 stress forces are;
-shear
-tension
-compression
1) Shear is the stress force that pushes back a mass of rock in two opposite directions which in turn will produce strike - slip faults.
2) Tension is the stress force that pulls on the crust thereby stretching in a manner that it becomes thinner at its middle which in turn will produce normal faults.
3) Compression is the stress force that makes rocks squeeze until they fold or break and this will in turn produce reverse faults.
HELPP ASAP PLEASE SEE IMAGES
Answer:
1st paragraph:
1.compound 2.physical 3.elements 4.water 5. gas 6.white 7. season 8.ratio 9.formula 10.elements 11.atoms 12.subscript 13.one
2nd paragraph
1.stable 2.many/reactive 3.eight 4.helium 5.seven 6.outer 7.one 8.level 9. compounds 10.reactive 11. seven 12. Eight 13.lose 14.gain 15. Share 16.compounds 17. atoms
Explanation:
I just did the 1st page. Gimme a min and I'll do the second.
I need help tutor it is hard
If you need help, ask a parent or teacher. Or yes, one of us can help! Just let us know what you're having trouble with, and we can see how we can help.
All matter is involved in motion of some kind. True or false
Answer:
true
Explanation: all matter down to the molecular or even atomic level has a constant vibration and movement. The only time that any matter could stop moving would be at absolute zero.
Help pls true or false
1. Oxygen from the lungs moves into the blood by active transport.
2. Osmosis requires no ATP energy
3. Active transport over time results in equilibrium
4. Oxygen, glucose, and carbon dioxide are not permeable to the cell membrane
5. In a salty environment, cells will decrease in volume and shrivel
Answer:
1 oxygen from the lungs
Explanation:
maybe too help you breath better
what is a substrate
Answer:
a substrate is surface or material on or from an organism lives, grows, or obtains its nourishment.
Explanation:
Hey I hope this helps.....
When water is heated a physical change occurs and it forms steam. When a lighted splint is applied to hydrogen gas, a chemical change occurs producing water in the form of steam. Explain how these two statements show two differences between physical and chemical changes.
Answer:
- A new substance was formed in the chemical change while no be substance was formed in the physical change
- The chemical change involved a change in chemical composition while the physical change involved no change in chemical composition
Please find the explanation below.
Explanation:
A physical change is a change that does not alter the chemical content of the substances involved, hence, no new substances are produced while a chemical change alters the chemical composition, hence, new substances results.
In this question,
- Water is heated till it forms steam is characterized as a physical change
- Lighted splint is applied to hydrogen gas to produce water in the form of steam is characterized as a chemical change.
- The first process is a PHYSICAL CHANGE because it involved only a change of state i.e. from liquid to gas, hence, no alteration to the chemical composition of the molecule and also no new substance is produced.
- The second process is a CHEMICAL CHANGE because there was a chemical combination of hydrogen gas and the oxygen in the lighted splint to yield water molecules ( a new substance). Therefore, it involved a chemical reaction and formation of a new substance
Which of the following salts has a 3 to 2 ratio of cations to anions?
O Barium Nitride
O Barium sulfide
Barium chloride
O Barium oxide
Explanation:
kind of ion formed (anion or cation) and the size of the ionic charge. ... O-‐2 oxide. S-‐2 sulfide. N-‐3 nitride. P-‐3 phosphide. Table 3.1. Common, simple anions. It is critically important that you distinguish between ...
Ions and Ionic Compounds – Introductory Chemistry – 1st Canadian Edition - BC Open Textbooks
opentextbc.ca › chapter › ions-and-ionic-...
The formula Na 2Cl 2 also has balanced charges, but the convention is to use the lowest ratio of ions, which ... For the ionic compound between magnesium cations (Mg 2+) and oxide anions (O 2−), again we need only ...
[PDF] Tutorial 2 FORMULAS, PERCENTAGE COMPOSITION, AND THE MOLE FORMULAS: A chemical formula shows the elemental composition of a sub
www.eiu.edu › eiuchem › forms › t...
Ba2+ barium. HSO3. – hydrogen sulfite. MnO4. – permanganate. Al3+ aluminum. SO4. 2– sulfate. NO2. – nitrite. Sn2+ tin(II). HSO4. – hydrogen sulfate. NO3. – nitrate. Sn4+ tin(IV). S2O3. 2– thiosulfate. OH– hydroxide.
Symbols and Charges for Monoatomic Ions
www.edu.xunta.es › portal › Nomenclature
Cs+ cesium ion O2- oxide. Be2+ beryllium ion S2- sulfide. Mg2+ magnesium ion Se2- ... one K+ and one Cl¯ are required. The resulting formula is KCl. Example 3: Write the formula from the following name: barium
Barium chloride salts has a 3 to 2 ratio of cations to anions. thus option C is correct.
what are the properties of barium chloride ?Barium Chloride an inorganic salt which is composed up of barium cations (Ba2+) and chloride anions (Cl–), otherwise named as Barium Muriate or Barium dichloride.
It is a white solid , water-soluble, hygroscopic and gives a slight yellow-green color to a flame, extensively used in the industry mainly The sulfate is used in white paints where as Barium chloride is poisonous in nature.
It is soluble in water which dissociate into barium cations and chloride anions in its dissolved state, However, the solubility of this compound in water is temperature-dependent.
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explain how to find the mass of water. show your calculations as well
Answer:
You can find the mass of water by multiplying the density of water by its volume.
mass = Density x volume
Explanation:
It is very easy to find the mass of water once you know the formula of density. "Density" refers to mass per unit volume.
Density (ρ) = [tex]\frac{mass}{volume}[/tex]
Therefore, mass = ρ x volume
The density of water is 1 kg/L.
For example, if the volume of water is 500 ml, then you can get its mass by multiplying 500 ml by 1 kg/L.
Let's convert 500 ml to Liter first.
500 ml x [tex]\frac{1 L}{1,000 ml}[/tex] = 0.5 L
Now, let's compute.
mass = ρ x volume
mass = 1 kg/L x 0.5L
mass = 0.5 kg
The mass of a 500-ml water is 0.5 kg.
A family consumes 2.5 gallons of milk per week. How many liters of milk do they need to buy for one month? (Assume there are exactly 4 weeks in 1 month) SHOW WORK
Answer:
37.85 liters
Explanation:
they need 10 gallons for a month (2.5*4)
after that, convert gallons to liters (conversion to liters= 3.785)
10*3.7585= 37.85
why is carbon dioxide a green house gas
Answer:
That's because the glass walls of the greenhouse trap the Sun's heat. The greenhouse effect works much the same way on Earth.
Explanation:
Gases in the atmosphere, such as carbon dioxide, trap heat just like the glass roof of a greenhouse. These heat-trapping gases are called greenhouse gases.
Which of the following is an example of a chemical property?
a. color
b. density
c. phase
d. the ability to rust
Compare the modern model of an atom to the atomic model proposed by John Dalton in 1805
Answer:
See explanation
Explanation:
Dalton's atomic theory furnished us with a basis to discuss the theory of atoms. However, not all his ideas holds up under the scruitiny of morden science.
He postulated that atoms were 'indivisible' the discovery of subatomic particles indeed show that there are smaller particles than atoms.
His postulation that atoms can neither be created nor destroyed does not hold water today because atoms are being created in nuclear reactors.
He said that atoms of all elements are exactly alike. Today we know there are isotopes of elements which are not exactly alike.
We can see that the Dalton's atomic theory did not take cognisance of the important role of subatomic particles in studying the structure of the atom. Modern atomic theory tries to look at the importance of these particles in the understanding the structure of the atom.
Why do scientists often use bacteria to produce medicines?
Answer:
Bbbbb eg2020
Explanation:
Bbbbb
What is the relationship between the circulatory and respiratory systems?
A. They work together to store the waste that blood collects from the body.
B. The circulatory system provides oxygen that the respiratory system uses to fill the lungs
C. The respiratory system provides blood that the circulatory system uses to transport nutrients.
D. They work together to supply oxygen to tissues and rid the body of carbon dioxide
Answer:
The circulatory and respiratory systems work together to circulate blood and oxygen throughout the body. Air moves in and out of the lungs through the trachea, bronchi, and bronchioles. Blood moves in and out of the lungs through the pulmonary arteries and veins that connect to the heart
Explanation:
This should help you out
4. What is the substance called that dissolves the other substance in a solution?
a. Soluto
b. Mixture
c. Solvent
d. Concentrator
Answer:
Solvent
Explanation:
When one substance dissolves into another, a solution is formed. A solution is a homogeneous mixture consisting of a solute dissolved into a solvent
please help. thank you!
Find an interesting chemical reaction. It can be a simple one but please have some facts and info about it. Thank you!
Answer:
Elephant Toothpaste
When hydrogen peroxide and potassium iodide are mixed in proper proportions, the hydrogen peroxide decomposes very quickly.The soapy water traps the oxygen, a product of the reaction, and creates many bubbles. Foam is a kind of a mixture called a colloid - gas bubbles in a liquid.It produces foam but it also can produce heat.Extra
Make Elephant Toothpaste
Pour 1/2 cup hydrogen peroxide solution, 1/4 cup dishwashing soap, and a few drops of food coloring into the bottle. Swish the bottle around to mix the ingredients. Set the bottle in a sink or outdoors or some other place where you won't mind getting wet foam everywhere.
In a separate container, mix a packet of active yeast with a little warm water. Give the yeast about five minutes to activate before proceeding to the next step.
When you are ready to do the demo, pour the yeast mixture into the bottle. The reaction occurs immediately upon the addition of the yeast.
I don't know if this will help but here you go.
(05 06 MC) The theoretical yields of Cl2 from certain starting amounts of MnO2 and HCl were calculated as 65.36 g and 68.08 g, respectively.
If the percentage yield of Cl2 is 70%, what is its actual yield?
42.25g
45.65g
46.33g
47.66g
Actual yield : 45.752 g ⇒no option
Further explanationGiven
The theoretical yields of Cl₂ : 65.35 g and 68.08 g
Required
The actual yield
Solution
Reaction
4 HCl (aq) + MnO₂ (s) → MnCl₂ (aq) + Cl₂ (g) + 2H₂O (l)
Because there are two theoretical yields, then we can choose the smallest one because the value is usually determined from the limiting reactant (in this reaction the limiting reactant is MnO₂)
So 65.36 g is The theoretical yields of Cl₂
Then the actual yield :
[tex]\tt \%yield=\dfrac{actual}{theoretical}\times 100\%\\\\actual=\%yield\times theoretical\\\\actual=70\%\times 65.36=45.752[/tex]