Answer:
D. 4
Explanation:
Answer and Explanation: Carbon can form a maximum of four covalent bonds. Carbon can share up to four pairs of electrons, therefore, the carbon atom fills its outer energy level and achieves chemical stability.
What is the solubility of 80 grams of magnesium chloride (MgCl2) dissolved into 150 cm3 of water?
A. 533.33g/dm3
B. 12g/dm3
C. 12000g/dm3
D. 1.88g/dm3
Answer:
A
Explanation:
10 g of a radioactive substance was placed in an air tight container 50 years ago. When the container was opened, only 2.5 g remains. What was the half life of this material?
Answer:
25 years.
Explanation:
From the question given above, the following data were obtained:
Original amount (N₀) = 10 g
Time (t) = 50 years
Amount remaining (N) = 2.5 g
Half-life (t½) =?
Next, we shall determine the number of half-lives that has elapse. This can be obtained as follow:
Original amount (N₀) = 10 g
Amount remaining (N) = 2.5 g
Number of half-lives (n) =?
N = 1/2ⁿ × N₀
2.5 = 1/2ⁿ × 10
Cross multiply
2.5 × 2ⁿ = 10
Divide both side by 2.5
2ⁿ = 10 / 2.5
2ⁿ = 4
Express 4 in index form with 2 as the base.
2ⁿ = 2²
n =2
Thus, 2 half-lives has elapsed.
Finally, we shall determine the half-life of the radioactive substance. This can be obtained as follow:
Time (t) = 50 years
Number of half-lives (n) = 2
Half-life (t½) =?
n = t / t½
2 = 50 / t½
Cross multiply
2 × t½ = 50
Divide both side by 2
t½ = 50 / 2
t½ = 25 years.
Thus, the half-life of the radioactive substance is 25 years.
if you understand please help me x
Answer:
1. Percentage yield is 64.75%
2. Atom economy is 48.39%
Explanation:
1. Determination of the percentage yield
Experimental yield = 24.8 g
Theoretical yield = 38.3 g
Percentage yield =?
Percentage yield = Experimental yield /Theoretical yield × 100
Percentage yield = 24.8 / 38.3 × Percentage yield = 2480 / 38.3
Percentage yield = 64.75%
2. Determination of the atom economy.
The balanced equation for the reaction is given below:
6CO₂ + 6H₂O —> C₆H₁₂O₆ + 6O₂
Next, we shall determine the mass of CO₂, H₂O and C₆H₁₂O₆ from the balanced equation.
Molar mass of CO₂ = 12 + (16×2)
= 12 + 32
= 44 g/mol
Mass of CO₂ from the balanced equation = 6 × 44 = 264 g
Molar mass of H₂O = (2×1) + 16
= 2 + 16
= 18 g/mol
Mass of H₂O from balanced equation = 6 × 18 = 108 g
Molar mass of C₆H₁₂O₆ = (6×12) + (12×1) + (6×16)
= 72 + 12 + 96
= 180 g/mol
Mass of C₆H₁₂O₆ from the balanced equation = 1 × 180 = 180 g
Next, we shall determine the total mass of the reactants. This is illustrated below:
Mass of CO₂ = 264 g
Mass of H₂O = 108 g
Total mass of reactants =?
Total mass of reactant = Mass of CO₂ + Mass of H₂O
Total mass of reactant = 264 + 108
Total mass of reactant = 372 g
Finally, we shall determine the atom economy. This can be obtained as follow:
Mass of desire atom (C₆H₁₂O₆) = 180 g
Total mass of reactants = 372 g
Atom economy =.?
Atom economy = mass of desire atom / total mass of reactant × 100
Atom economy = 180/372 × 100
Atom economy = 48.39%
DOES ANYONE KNOW THESE?? :(
Answer and Explanation:
9. Gas particles are always in constant and C. Random motion.
10. In a sample of a gas, most of the volume is B. Empty Space.
11. Which state of matter has constant shape and volume?
A. Solid
12. A solid is a state of matter that has a B. Definite Volume and Definite Shape.
13. In which state of matter are particles packed together in fixed positions?
B. Solid
#teamtrees #PAW (Plant And Water)
Aldehydes and ketones are converted into alkenes by means of a direct nucleophilic addition called the Wittig reaction.
a. True
b. False
Answer:
The given statement- Aldehydes and ketones are converted into alkenes by means of a direct nucleophilic addition called the Wittig reaction, is True.
Explanation:
The Wittig reaction converts aldehydes and ketones into alkenes through a simple nucleophilic addition. A triphenylphosphorine ylide, also known as a phosphorane, reacts with an aldehyde/ketone to produce an oxaphosphetane, a four-membered cyclic intermediate. Instead of being isolated, the oxaphosphetane decomposes spontaneously to release triphenylphosphine oxide and an alkene.
In an SN2 reaction, triphenylphosphine, a good nucleophile, reacts with a primary alkyl halide, followed by deprotonation of the carbon with a solid base, such as butyllithium, to form the ylide. In the product alkene, the carbonyl carbon and the carbon initially bound to the halogen become two carbons with a double bond.
The Wittig reaction's true worth lies in its ability to produce an alkene with a predictable structure, as the C=C bond forms exactly where the C=O bond did in the reactant, with no isomers (other than E/Z isomers) forming.
Hence , the correct option is (A) True.
Moby eats three-sixths of a pizza. Which fraction is equivalent to three-sixths?
Answer:
1/2
Explanation:
Half of 6 is 3 so therefore it is a half.
6 The final process in the formation of sedimentary rock is - A. cementation B. melting C.cooling
Answer:
A. cementation
Explanation:
( it deleted my answer)
Name 2 physical properties that would allow differentiation between copper, lead and iron shot.
Answer:
Two physical properties that would allow differentiation between copper, lead and iron shot are - Color and Density
COPPER - Color - Copper has a reddish brown color .
Density - Density of copper is 8.96 [tex]g/cm^{3}[/tex]
LEAD - Color - Lead is grey in color.
Density - Density of Lead is 11.34[tex]g/cm^{3}[/tex]
IRON SHOT - Color- Iron shot is in grey color with extra shine .
Density - Density of iron shot is 10.49 [tex]g/cm^{3}[/tex]
Explanation:
COPPER- Copper (Cu) is a reddish, highly ductile metal that belongs to Group 11 (Ib) of the periodic table and is a particularly excellent conductor of electricity and heat. Copper is found in nature in its free metallic state.
LEAD- Lead (Pb) is a soft, silvery white or grayish metal in Periodic Group 14 (IVa). Lead is a weak conductor of electricity and is very malleable, ductile, and thick. Lead, which has been known since antiquity and is considered the oldest of metals by alchemists, is extremely durable and corrosion-resistant, as evidenced by the continued use of lead water pipes constructed by the ancient Romans.
IRON SHOT - Small round iron balls used as projectiles are known as iron shot. Balance scales are used with simple weights. Iron balls are used in the shot put competition.
Hence , the differentiation is mentioned in the above answer.
The electron affinity of an element is positive if energy is absorbed during the process of accepting an electron and negative if energy is released during the process. Using the electron configuration of the atom or ion undergoing the addition of an electron, predict whether the electron affinity will be positive or negative for the following reactions, and classify them accordingly.
Na(g)+ 1e^- → Na^-(g)
Mg(g)+1e^- → Mg^-(g)
Br(g)+ 1e^- → Br^-(g)
Answer:
See explanation
Explanation:
Electron affinity is the energy released when an extra electron is added to a neutral gaseous atom. A negative value of electron affinity indicates that energy is given out and vice versa.
Metals have positive electron affinity since electrons rarely accept electrons, so;
Na(g)+ 1e^- → Na^-(g) positive
Mg(g)+1e^- → Mg^-(g) positive
For the last case; Br(g)+ 1e^- → Br^-(g), the electron affinity for the non-metals is negative. hence the answer
what was the name of yesterday's supermoon
Answer: May's full moon or Flower moon
Explanation:
When a sample of gas was placed in a sealed container with a volume of 3.35 L and heated to
75°C, the gas vaporized and the resulting pressure inside the container was 17atm. How
many moles of the gas were present?. Single line text.
Answer:
Explanation:What is the demand factor for three commercial ranges?
How does a duckling become a bigger and stronger adult duck?
A. Body repair
B. Warmth
C. Growth
D. Motion
Answer:The correct answer is C.
Explanation: I had it on a quiz
Answer: the answer is C growth
Explanation: body repair, motion and warmth are not the answer the reason why is because body repair is when the body repairs it’s self if it’s hurt and motion is when animals use the energy from the food they eat to move and warmth helps animals to get warm so they don’t get to cold so the answer would be growth .
what is conductor?
give two examples.
Answer:
Conductor is any material tht allows he flow of electrons or electric current . Ex: Metals like iron and copper.
Hope im right!!
Answer:-
Examples of conductors include metals, aqueous solutions of salts (i.e., ionic compounds dissolved in water), graphite, and the human body. Examples of insulators include plastics, Styrofoam, paper, rubber, glass and dry air.sea stars have radial symmetry .what does this mean?
Answer: Echinoderms usually have five appendages (arms or rays), but there are some exceptions. Radial symmetry means that the body is a hub, like a bicycle wheel, and tentacles are spokes coming out of it (think of a starfish).
Explanation:
Answer:
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Explanation:
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A solution contains 6 mg isopropanol dissolved in 2 kg H2O. The isopropanol concentration is
a.3% isopropanol.
b.3 M isopropanol.
c.3 m isopropanol.
d.3 ppm isopropanol.
Answer:
Option D. 3 ppm isopropanol
Explanation:
The following data were obtained from the question:
Mass of isopropanol = 6 mg
Mass of water = 2 Kg
Isopropanol concentration =?
The isopropanol concentration can be obtained as follow:
Concentration = mass isopropanol / mass of water
Isopropanol concentration = 6 mg / 2 kg
Isopropanol concentration = 3 mg/Kg
Finally, we shall convert 3 mg/Kg to ppm. This can be obtained as follow:
1 mg/Kg = 1 ppm
Therefore,
3 mg/Kg = 3 ppm
Thus, we can conclude that the concentration of isopropanol is 3 ppm.
Why is it that the higher the molecular mass of the alkane, the higher the boiling point? Refer to intermolecuar forces and energy.
Answer:
Higher melting and boiling points signify stronger noncovalent intermolecular forces. Consider the boiling points of increasingly larger hydrocarbons. More carbons means a greater surface area possible for hydrophobic interaction, and thus higher boiling points.
Calculate the molecular weight of guanylate at pH 7. Show your work. Draw the structures of three different tautomers of hypoxanthine. One of the nonstandard nucleotides that appears moderately often in rRNA and tRNA is dihydrouridine. Which carbon atoms within the uracil moiety of this nucleotide have two hydrogens each attached to them
Answer:
Explanation:
The molecular formula for Guanylate is [tex]\mathbf{C_{10} H_{14} N_5O_8 P}[/tex]
This is calculated by the addition of the atomic weight of all the atoms taking part in the molecule.
i.e. (10 × C) + (14 × H) + (5 × N) + ( 8 × O) + (1 × P)
= (10 × 12) + (14 × 1) + (5 × 14) + ( 8 × 16) + (1 × 30)
= 120 + 14 + 70 + 128 + 30
= 362 g/mol
The diagram for the tautomers of hypoxanthine can be seen in the image attached below.
Dihydrouridine is available and can be seen in tRNAs and rRNAs. It is an exceptionally preserved and adjusted base. It is a pyrimidine nucleoside that is shaped by the expansion of two hydrogen atoms to uridine. By the expansion of two hydrogen atoms to uridine makes it completely soaked and no presence of any two-fold or double bond.
Catalytic reduction of carbon-carbon double bonds in Dihydrouridine synthase occurs at positions 5 and 6 on the uridine base.
Hence, 5 and 6 carbon particles inside the uracil moiety of this nucleotide have two hydrogens each connected to them.
Which transformation represents light energy transforming into chemical energy?
A. turning on an electrical lamp
B. turning on a stove to heat dinner
C. growing an apple tree from seed
D. making toast in an electric toaster
Reduction of methanal equation
Answer:
hi
Explanation:
than you for points and thank me if you like
Nitric oxide gas, NO(g), can be oxidized in air to
produce nitrogen dioxide gas, NO2(g):
2 NO(g) + O2(g) → 2 NO2(g)
Determine the enthalpy change for this reaction
using any of these thermochemical equations:
02(g) →20(g)
AH = +495 kJ
Hope this helps!!
Thank You!
what is the 24 g of H2O
Explanation:
H2O 1 mol = (2H + O)
= 2(1) + 16
= 2 + 16 = 18 g
H2O 18 g = 1 mol
H2O 24 g = 1/18 × 24 = 1.33 mol
what is the percent of chloride ion in a sample if 1.1324g of the sample produces 1.0881 of AgCl when treated with exess Ag+?
According to the percent composition concept, the percent of chloride ion is 96.07%.
What is percent composition?Percent composition is defined as a convenient way to record concentration of solution.It is a expression which relates solute to solvent as,mass of solute/mass of solution ×100.There are two types of percentage compositions percent weight by volume and percent volume by volume .Advantages of using percent compositions is that molecular weight of compound is not required.
In the given example, percent of chloride ion is estimated as, mass of chloride ion/mass of AgCl×100
On substitution in above formula, percent composition=1.0881/1.1324×100=96.07%.
Thus, the percent of chloride ion is 96.07%.
Learn more about percent composition,here:
https://brainly.com/question/17505281
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A sample of hydrogen gas occupies
1.0 L at 760 torr in a balloon. If the
temperature is kept constant, which
expression represents the volume of
hydrogen gas in liters when the
pressure is raised to 860 torr?
A 860 + 760
B 860 – 760
C 860 / 760
D 760 / 860
When the pressure of a sample of hydrogen gas increases from 760 torr to 860 torr, the expression D 760 / 860 represents the volume of hydrogen gas in liters.
What does Boyle's law state?Boyle's law is a law stating that the pressure of a given mass of an ideal gas is inversely proportional to its volume at a constant temperature.
A sample of hydrogen gas occupies 1.0 L at 760 torr in a balloon. We can calculate the volume when the pressure is increased to 860 torr using Boyle's law.
P₁ × V₁ = P₂ × V₂
V₂ = (P₁/P₂) × V₁
V₂ = (760 torr/860 torr) × 1.0 L = 0.88 L
where,
P₁ and V₁ are the initial pressure and volume.P₂ and V₂ are the final pressure and volume.When the pressure of a sample of hydrogen gas increases from 760 torr to 860 torr, the expression D 760 / 860 represents the volume of hydrogen gas in liters.
Learn more about Boyle's law here: https://brainly.com/question/469270
Which of the following processes is endothermic?
Any combustion reaction
Bonds being made in the products
Bonds being broken in the reactants
what statement best explains how life functions a unicellular organism are carried out?
Answer:
C). The structures in the cell work together to perform its life functions.
Explanation:
Unicellular organisms are characterized as organisms that are able to perform all the life functions through a single-cell. The third statement correctly elaborates how 'single-celled organisms carry out these life functions by cooperatively employing the structures lying inside the cell.' The first option is incorrect as it talks about multi-cells which doesn't even exist in unicellular organisms. While the second option is wrong because there are no tissues formed of single-cell. The last option is incorrect as the specialized cells perform different life functions in multi-cellular organisms. Thus, option C is the correct answer.
Answer:
The structures in the cell work together to perform its lifefunctions.
Explanation:
Predict what will be observed in each experiment below. experiment predicted observation.
1. A student sees tiny bubbles clinging to the inside of an unopened plastic bottle full of carbonated soft drink. The student squeezes the bottle.
a. The bubbles will shrink, and some may vanish.
b. The bubbles will grow, and more may appear.
c. The bubbles won't change.
d. I need more information to predict what will happen to the bubbles.
2. A student has two unopened cans containing carbonated water. Can A has been stored in the garage () and can B has been stored in the fridge (). The student opens one can at the time, both cans make a fizz.
a. Can A will make a louder and stronger fizz than can B.
b. Can B will make a louder and stronger fizz than can A.
c. The fizz will be the same for both cans.
d. There is not enough information to predict which can will make the louder fizz.
Answer:
The correct answer is -
1. a) The bubbles will shrink, some may vanish.
2. a) Can A will make a louder and stronger fizz than can B.
Explanation:
In the first question, it is given that the bottle is not opened and therefore, squeezing the bottle filled with a carbonated drink will increase the pressure on the carbonated liquid which forces the bubbles to dissolve or displace or vanish as it moves to empty space.
Thus, the correct answer would be - The bubbles will shrink, some may vanish
In the second question, there are two different conditions for two different unopened cans of carbonated water that are different temperatures one at the garage with higher temperature and one in the fridge at low temperature. As it is known that higher the temperature less will be solubility of gas in liquid so gas in can A will be less soluble which means it has more gas and it will make louder and stronger fizz than B which was stored at low temperature.
thus, the correct answer would be - Can A will make a louder and stronger fizz than can B.
2. The approximate concentration of hydrochloric acid, HCl, in the stomach (stomach
acid) is 0.17M. Calculate the mass of the following antacids required to neutralize 50cm of
stomach acid.
(a) Bicarbonate of soda NaHCO3
(b) Aluminum hydroxide, Al(OH)3
Please .
Answer:
a) 0.714g of bicarbonate of soda are required.
b) 0.221g of Al(OH)₃ are required
Explanation:
The reactions of HCl with bicarbonate of soda and aluminium hydroxide are:
HCl + NaHCO₃ → H₂O + NaCl + CO₂
3 HCl + Al(OH)₃ → 3H₂O + AlCl₃
The moles of HCl that we need neutralize are:
50mL = 0.050L * (0.17mol / L) = 0.0085 moles HCl
To solve these problem we need to find the moles of the antacid using the chemical reaction and its mass using its molar mass;
a) Moles NaHCO₃ = Moles HCl = 0.0085 moles
The mass is -Molar mass NaHCO₃: -84g/mol-
0.0085 moles * (84g / mol) = 0.714g of bicarbonate of soda are required
b) 0.0085 moles HCl * (1mol Al(OH)₃ / 3mol HCl) = 2.83x10⁻³ moles Al(OH)₃
The mass is -Molar mass: 78g/mol-:
2.83x10⁻³ moles Al(OH)₃ * (78g/mol) =
0.221g of Al(OH)₃ are requiredHelp please thank you
Answer:
It’s probably plants seed and raise crops for their food
Explanation:
Answer:
I would say b
Explanation:
A hunter would go out to hunt and gathers handle crops or find crops so b.
chemistry semester 2
35 points plz be fr will mark brainliest
Answer:
6. solar eclipsis
7. drive less fuel efficient vehicles
Explanation:
these are the only questions i get but i still hope this helps :)