Answer:
Throughout the explanations section below you will find a description of the question.
Explanation:
(1)
Whether a solution would be positioned inside a separative funnel, combined water, as well as solvent, disintegrate particulate caffeine. In every stage, the caffeine content incorporated relies upon the coefficient of caffeine partitioning throughout the combination of water as well as fluid.Thus, increasingly caffeine is taken from the solvent whenever the moment you bring additional solvent. Consequently, we separate the solvent from the single component.(2)
For compounds to be mixed thoroughly and separated into different layers, a shuddering mixture within the dividing funnel would be essential.However, it vibrates the separation funnel forcefully, restricts airflow within the funnel, which can also induce the fluid under it to burst or causing fluid to fire.To insert a thermometer into an adapter, use ______ to prepare the thermometer. Then, hold the thermometer ______ the adapter and _____ the thermometer into the adapter.
Answer:
mineral oil; close to; slowly turn
Explanation:
Temperature can be defined as a measure of the degree of coldness or hotness of a physical object. It is measured with a thermometer and its units are Celsius (°C), Kelvin (K) and Fahrenheit (°F).
Generally, temperature measures the average kinetic energy of particles in a particular substance.
A thermometer can be defined as a device used for measuring the temperature (degree of hotness or coldness) of a body or substance is. It is a thin glass having a bulb on one of its end and typically contains either colored alcohol or mercury.
A thermometer adapter is used with a temperature probe in the distillation process, in order to determine readings.
To insert a thermometer into an adapter, use mineral oil to prepare or make suitable the thermometer. Then, hold the thermometer close to the adapter and slowly turn the thermometer into the adapter.
Which one of the following compounds shows red precipitate of Cu2O with the reaction of Fehling solution?
a. Vinegar c. Glycerine
b. Formalin d. Propanon
Answer:
acetaldehyde
When acetaldehyde is heated with Fehling's solution, a red precipitate is formed.
Explanation:
When sugar is added to a sugar solution, the sugar dissolves. Which term describes the original sugar solution?
Answer:
the answer is D .................
A student measured the gram weight of a metal object to be 5.88g. According to the supplier the object weighs 5.97g. What is the error in the student's measurement?
A. -0.09
B. +0.09
Answer:
–0.09
Explanation:
From the question given above, the following data were obtained:
Measured value = 5.88 g
Actual value = 5.97 g
Error =?
The error in the student's measurement can be obtained as follow:
Error = Measured value – Actual value
Error = 5.88 – 5.97
Error = –0.09
Therefore, the error in the student's measurement is –0.09
Organic foods do not contain chemicals.
True
Or
False
Answer:
True
Explanation:
The word Organic refers to the methods used to cultivate and process farm agricultural products. Organic foods are edible and nutritious substances consumed (both plants and animals) that are free from the use of synthetics and chemicals. In plants, the include the use of organic manure that serves as fertilizers and carrying out the weeding process by hand weeding. In animals, diseases can be prevented by maintaining a clean house or rotational grazing.
The benefit of organic foods are to produce food substances with no chemical substances.
According to Newton's law of universal gravitation, how do the masses of two
objects relate to the gravitational force between them?
A. As either mass increases, the gravitational force between them
increases.
B. As either mass increases, the gravitational force between them
decreases.
C. Gravitational force increases only when both masses increase.
D. Gravitational force increases only when both masses decrease.
Answer:
As either mass increases, the gravitational force between them
increases.
Explanation:
According to Newton's law of universal gravitation;
F α m1m2/r^2
That is, the force between two masses in a gravitational field is directly proportional to the product of the two masses and inversely proportional to their distance apart.
Hence, as either of the masses increase, the force of gravitation between the two masses increases. Hence the answer.
A 1.19 g sample of an unknown halogen occupies 109 mL at 398 K and 1.41 atm. What is the identity of the halogen
Answer:
The halogen is Iodine.
Explanation:
Using the ideal gas equation, we find the number of moles of gas present, n.
PV = nRT where P = pressure of gas = 1.41 atm, V = volume of gas = 109 mL = 0.109 L, n = number of moles of gas, R = molar gas constant = 0.082 L-atm/mol-K and T = temperature of gas = 398 K
Since PV = nRT, making n subject of the formula, we have
n = PV/RT
substituting the values of the variables into the equation, we have
n = 1.41 atm × 0.109 L/(0.082 L-atm/mol-K × 398 K)
n = 0.15369 atm-L/32.636 L-atm/mol
n = 0.0047 mol
Since n = m/M where m = mass of gas = 1.19 g and M = relative molecular mass of gas
So, M = m/n
M = 1.19 g/0.0047 mol
M = 252.7 g
Since halogens are diatomic the relative atomic mass is M/2 = 252.7g/2 = 126.34 g
From tables, the only halogen with this atomic mass is Iodine.
So, the halogen is Iodine.
Name the compound CuI2
Answer:
Copper iodide. I think
Answer:
copper iodide(Cul2)hope it helps
stay safe healthy and happy..How many doubtful digit(s) is/are allowed in any measured quantity?
(Only 3 choices.)
A.) 1
B.) 2
C.) zero
Answer:
zero
Explanation:
I I think one should be so accurate with measurements and experiments
Given 200ul of a 0.5mg/ml stock solution of BSA, how much do you pipet into a test tube so that you are adding 5ug of BSA to the test tube
Answer: [tex]10\mu L[/tex] of volume needs to be pipetted out in the test tube.
Explanation:
We are given:
Mass of BSA to be formed = [tex]5\mu g=0.005mg[/tex] (Conversion factor: [tex]1mg=1000\mu g[/tex]
Volume of stock solution = [tex]200\mu L=0.2mL[/tex] (Conversion factor: [tex]1mL=1000\mu L[/tex]
It is also given that for the mass of BSA is 0.5 g, the volume used up is 1 mL
In order to have, 0.005 g, the volume of stock solution needed will be = [tex]\frac{1mL}{0.5g}\times 0.005g=0.01mL=10\mu L[/tex]
Hence, [tex]10\mu L[/tex] of volume needs to be pipetted out in the test tube.
Question 4 of 30
Scientific research shows that Earth's climate is changing due to human
activities. How can scientific research on climate change help society?
A. It can help us stop storms before they occur.
B. It can help us find a new way to make more water.
C. It can help us track how quickly elements of the climate are
changing
D. It can help us reverse the effects of climate change.
th
C. It can help us track how quickly element of the climate are changing
c) Solar energy is the source of all forms of energy.give reasons
Answer:
All energy is made by the sun because without the sun there would be no humans to produce other energy
Explanation:
We use many different forms of energy here on earth, but here’s the thing: almost all of them originate with the sun, not just light and heat (thermal) energy! The law of conservation of energy says that energy can’t be created or destroyed, but can change its form. And that’s what happens with energy from the sun—it changes into lots of different forms:
Plants convert light energy from the sun into chemical energy (food) by the process of photosynthesis. Animals eat plants and use that same chemical energy for all their activities.
Heat energy from the sun causes changing weather patterns that produce wind. Wind turbines then convert wind power into electrical energy.
Hydroelectricity is electrical energy produced from moving water, and water flows because heat energy from the sun causes evaporation that keeps water moving through the water cycle.
Right now, much human activity uses energy from fossil fuels such as coal, oil, and natural gas. These energy sources are created over very long periods of time from decayed and fossilized living matter (animals and plants), and the energy in that living matter originally came from the sun through photosynthesis.
solar panel shows what is the ultimate source of energy
discuss the benefits of observing good safety measures in relation to increase in productivity within a pharmaceutical laboratory?
Answer:
Pharmaceutical laboratory helps in devloping and conducting research, vaccines. Various kinds of drugs and chemical substances used and are produced at a Pharmaceutical laboratory.
The pharmaceutical laboratories performs with various hazardous substances that results in exposure to various chemicals, biological substances and radiation. To avoid any injury or infection labs need to maintain all safety measures.
Spillage and relaseing chemical substances can be lethal during transportaions by safety measures for heling in for manufacturing of such therapeutic agents spillage and avoid wastage.
Maintaining good safety standards in the pharmaceuticals laboratory will help promote the health of technicians and workers which in turn will increase productivity and attain positive outcomes.
The action of some commercial drain cleaners is based on the following reaction:
2 NaOH(s) + 2 Al(s) + 6 H2O(l) â 2 NaAl(OH)4(s) + 3 H2(g)
What is the volume of H2 gas formed at STP when 4.32 g of Al reacts with excess NaOH?
A. 3.59 L
B. 2.39 L
C. 5.87 L
D. 5.38 L
Answer:
5.38 L
Option D.
Explanation:
2 NaOH(s) + 2 Al(s) + 6 H₂O(l) → 2 NaAl(OH)₄(s) + 3 H₂(g)
We convert mass of Al to moles:
4.32 g . 1 mol /26.98g = 0.160 moles
As NaOH is in excess, aluminum is the limiting reactant.
We see stoichiometry, were ratio is 2:3.
2 moles of Al can produce 3 moles of hydrogen
Our 0.160 moles may produce (0.160 . 3)/2 = 0.240 moles of H₂.
We know that 1 mol of any gas at STP conditions is contained in 22.4L
So let's make the conversion factor:
0.240 mol . 22.4L / 1mol = 5.38 L
Plz help me ASAP in my final project I am ready to pay 20$
Answer:
what do you need help with
A calorimeter measures the ______ involved in reactions or other processes by measuring the ______ of the materials _____ in the process. The calorimeter is _______ to prevent transfer of heat to outside the device.
Answer:
heat; temperature; surrounding; insulated.
Explanation:
A calorimeter can be defined as a scientific instrument or device designed and developed for measuring the heat involved in reactions or other processes, especially by taking the measurement of the temperature of the materials surrounding the process.
Basically, a calorimeter is insulated using materials with very high level of resistivity so as to prevent heat transfer to the outside of the device (calorimeter). Some of the components that make up a simple calorimeter are thermometer, an interior styrofoam cup, an exterior styrofoam cup, cover, etc.
Additionally, a calorie refers to the amount of heat required to raise the temperature of a gram of water by one degree Celsius (°C).
Determine the percentage of carbon and hydrogen in ethane C2H6 if the molecular weight is 30.
Answer:
Percentage of carbon:
[tex] { \tt{ = \frac{24}{30} \times 100\%}} \\ = 80\%[/tex]
Percentage of hydrogen:
[tex]{ \tt{ = \frac{6}{30} \times 100\%} } \\ = 20\%[/tex]
Explain why the balls representing fluorine (teal) and hydrogen (white) have only one peg, while carbon (black) has four.
Answer:
Hydrogen and fluorine form only one bond while carbon forms four bonds to other atoms.
Explanation:
This question brings us to the idea of valency. Fluorine is univalent while carbon is tetravalent.
Univalent means that fluorine can only form one bond to hydrogen while carbon forms as much as four bonds because it is tetravalent.
Hence fluorine and hydrogen have only one peg while carbon has four.
How many miles are in 8.73 *10^25 atoms of boron
The correct question is: How many moles are in [tex]8.73 \times 10^{25}[/tex] atoms of boron.
Answer: There are 145 moles present in [tex]8.73 \times 10^{25}[/tex] atoms of boron.
Explanation:
According to the mole concept, there are [tex]6.022 \times 10^{23}[/tex] atoms present in one mole of every substance.
Hence, number of moles present in [tex]8.73 \times 10^{25}[/tex] atoms is calculated as follows.
[tex]Moles = \frac{8.73 \times 10^{25}}{6.022 \times 10^{23}}\\= 1.45 \times 10^{2}\\= 145 mol[/tex]
Thus, we can conclude that there are 145 moles present in [tex]8.73 \times 10^{25}[/tex] atoms of boron.
The elemental mass percent composition of succinic acid is 40.68% CC, 5.12% HH, and 54.19% OO. Determine the empirical formula of succinic acid.
Answer:
C2H3O2
Explanation:
Empirical formula is defined as the simplest whole-number ratio of atoms present in a molecule. To solve this question we need to convert the percentage of each atom to moles using molar mass. With the moles of each atom we can find the ratio:
Moles C -Molar mass: 12.01g/mol-
40.68g * (1mol/12.01g) = 3.387 moles C
Moles H-Molar mass:1g/mol-:
5.12g * (1mol/1g) = 5.12 moles H
Moles O -Molar mass: 16g/mol-
54.19g * (1mol/16g) = 3.387 moles O
Ratio of atoms (Dividing in moles of C that are the lower number of moles):
C = 3.387 moles C / 3.387moles C = 1
H = 5.12moles H / 3.387moles C = 1.5
O = 3.387moles O / 3.387 moles C = 1
This ratio twice (To have only whole-numbers):
C = 2
H = 3
O = 2
Empirical formula of succinic acid:
C2H3O2Consider an acid-base titration in which the base is dispensed from a burette into a flask containing an acid. If any drops of the base adhere to the inner walls of the flask, but do not actually mix with the solution, the calculated acid concentration would be
Answer:
Higher than the actual value
Explanation:
Titration is a volumetric process in which a known volume of solution is dispensed from a burette to react with a known volume of solution in a conical flask.
When acid-base titration is carried out in such a way that the base is in the burette and the acid is in the conical flask and drops of the base adhere to the inner walls of the flask, but do not actually mix with the solution, the calculated acid concentration would be higher than the actual value.
This is because;
From CA= CBVBnA/VAnB
When VB(volume of base) that reacted is lower than the actual volume recorded, then the calculated volume of CA(concentration of acid) is much higher than the actual value since drops of the base adhere to the inner walls of the flask.
Suppose, in an experiment to determine the amount of sodium hypochlorite in bleach, you titrated a 23.92 mL sample of 0.0100 M K I O 3 with a solution of N a 2 S 2 O 3 of unknown concentration. The endpoint was observed to occur at 13.80 mL . How many moles of K I O 3 were titrated
Answer:
2.39x10⁻⁴ moles
Explanation:
As the problem asks us the number of moles of KIO₃ that were titrated, all that is required of us is to calculate how many moles of KIO₃ are there in 23.92 mL of a 0.0100 M solution (All moles in the samples are titrated).
We can do so by using the definition of molarity:
Molarity = moles / litersconverting 23.92 mL ⇒ 23.92 / 1000 = 0.02392 L
moles = 0.0100 M * 0.02392 Lmoles = 2.39x10⁻⁴ molesThe addition of chromic acid or chromate is a qualitative test for alcohols as the reaction causes a color change. However, not all alcohols react with chromic acid or chromate. Determine whether the named alcohol will react with chromic acid or chromate to cause a color change.
a. 3-hexanol
b. 1 -butanol
c. 2-pentanol
d. 3-ethyl-3-pentanol
Answer:
3-hexanol
1 -butanol
2-pentanol
Explanation:
Let us recall that chromic acid or chromate are strong oxidizing agents. When they are oxidized, their colour changes from orange to green.
This shows a reduction in chromic acid or chromate. The reaction of chromic acid or chromate with a primary alcohol yields a carboxylic acid while reaction with a secondary substrate yields an alkanal.
Note that Tertiary alkyl halides are not be oxidized hence reactions involving a point where invitation carried along occur.
3-ethyl-3-pentanol is a tertiary alkyl halide hence it can not be oxidized.
define a molecular mass and mole
Answer:
A molecular mass is mass on the substance and mole is a unit of substance such as atoms and electrons.
Explanation:
A molecular mass is the mass of a molecule of the substance and is called as molecular weight. Molar mass is measured in moles. Mass of one mole is 6.022x10²³ particles and is expressed in grams. The molar mass is said to be the mass of the given substance that is divided by the amount of the substance and s expressed in g/ml.Molecular mass: A molecule's molecular mass is equal to the sum of all of the atoms' individual atomic masses. It establishes the molecular mass of a single unit.
Example:
Molecular mass of O2 = 32 atomic mass units
Mole: A mole is [tex]6.02214076 x 10^2^3[/tex]of any chemical unit, including atoms, molecules, ions, and others. Due to the large number of atoms, molecules, or other components that make up any material, the mole is a useful measure to utilize. The initial definition of the mole was the number of atoms in 12 grams of carbon-12.
Learn more about mole here:https://brainly.com/question/22540912
define the following terms atom
22. Glycerol, C3H8O3, is a substance used extensively in the manufacture of cosmetics, foodstuffs, antifreeze, and plastics. Glycerol is a water-soluble liquid with a density of 1.2656 g/mL at 15 0C. Calculate the molarity of a solution of glycerol made by dissolving 50.000 mL glycerol at 15 0C in enough water to make 250.00 mL of solution. Show work.
Answer:
2.75M
Explanation:
Density = mass/volume
Density of glycerol (C3H8O3) at 15°C is given as 1.2656 g/mL.
Volume of glycerol at this same temperature before dissolving in water = 50mL
Hence, using Density = mass/volume
1.2656 = mass/50
mass = 1.2656g/mL × 50mL
mass = 63.28g
Molarity of solution = number of moles (n) ÷ volume (V)
Volume of glycerol dissolved in water = 250mL = 0.250L
number of moles = mass/molar mass
Molar mass of C3H8O3 = 12(3) + 1(8) + 16(3)
= 36 + 8 + 48
= 44 + 48
= 92g/mol
n = 63.28g ÷ 92g/mol
n = 0.688mol
* Molarity = n/V
Molarity = 0.688/0.250
Molarity = 2.75M
Aqueous hydrochloric acid will react with solid sodium hydroxide to produce aqueous sodium chloride and liquid water . Suppose 35. g of hydrochloric acid is mixed with 73.0 g of sodium hydroxide. Calculate the minimum mass of hydrochloric acid that could be left over by the chemical reaction. Round your answer to significant digits.
Answer:
No mass of HCl could be left over by the chemical reaction because is the limting reactant and it is all consumed.
Explanation:
Our reactants are: HCl and NaOH
Products are: NaCl and H₂O
This is a neutralization reaction that can also be called an acid base reaction, an acid and a base react to produce water and a neutral salt, in this case where we have strong acid and base.
Ratio is 1:1. We convert mass to moles:
35 g . 1 mol / 36.45 g = 0.960 moles of HCl
73 g . 1 mol / 40 g = 1.82 moles of NaOH
As ratio is 1:1, for 0.960 moles of HCl we need 0.960 moles of NaOH and for 1.82 moles of NaOH, we need 1.82 moles of acid.
As we only have 0.960 moles of HCl and we need 1.82 moles, no acid remains after the reaction goes complete. HCl is the limiting reactant, so the acid, it is all consumed.
Aqueous hydrobromic acid (HBr) will react with solid sodium hydroxide (NaOH) to produce aqueous sodium bromide (NaBr) and liquid water (H2O). Suppose 5.7 g of hydrobromic acid is mixed with 0.980 g of sodium hydroxide. Calculate the maximum mass of water that could be produced by the chemical reaction. Round your answer to significant digits.
Answer:
The maximum mass of water that could be produced by the chemical reaction=0.441g
Explanation:
We are given that
Given mass of HBr=5.7 g
Given mass of sodium hydroxide=0.980 g
Molar mass of HBr=80.9 g/ Mole
Molar mass of NaOH=40 g/mole
Molar mass of H2O=18 g/mole
Reaction
[tex]HBr+NaOH\rightarrow H_2O+NaBr[/tex]
Number of moles=[tex]\frac{given\;mass}{molar\;mass}[/tex]
Using the formula
Number of moles of HBr=[tex]\frac{5.7}{80.9}=0.0705 moles[/tex]
Number of moles of NaOH=[tex]\frac{0.980}{40}=0.0245moles[/tex]
Hydrogen bromide is in a great excess and the amount of water produced.
Therefore,
Number of moles of water, n(H2O)=Number of moles of NaOH=0.0245moles
Now,
Mass of water=[tex]n(H_2O)\times Molar\;mass\;of\;water[/tex]
Mass of water=[tex]0.0245moles\times 18=0.441g[/tex]
Hence, the maximum mass of water that could be produced by the chemical reaction=0.441g
Na2CO3 reacts with dil.HCl to produce NaCl, H2O and CO2. If 21.2 g of pure Na2CO3 are added in a solution containing 21.9g HCl , a. Find the limiting reagent. (2) b. Calculate the number of moles of excess reagent left over.(2) c. Calculate the number of molecules of H2O formed.(1) d. Calculate volume of CO2 gas produced at 270C and 760mm Hg pressure.(2) e. Write significance of limiting reagent
Answer:
See explanation
Explanation:
Equation of the reaction;
Na2CO3(aq) + 2HCl(aq) -------> 2NaCl(aq) + H2O(l) + CO2(g)
Number of moles of Na2CO3 = 21.2g/106g/mol = 0.2 moles Na2CO3
Number of moles of HCl = 21.9g/36.5g/mol = 0.6 moles of HCl
1 mole of Na2CO3 reacts with 2 moles of HCl
0.2 moles of Na2CO3 reacts with 0.2 × 2/1 = 0.4 moles of HCl
Hence Na2CO3 is the limiting reactant
Since there is 0.6 moles of HCl present, the number of moles of excess reagent=
0.6 moles - 0.4 moles = 0.2 moles of HCl
1 mole of Na2CO3 forms 1 mole of water
0.2 moles of Na2CO3 forms 0.2 moles of water
Number of molecules of water formed = 0.2 moles × 6.02 × 10^23 = 1.2 × 10^23 molecules of water
1 mole of Na2CO3 yields 1 mole of CO2
0.2 moles of Na2CO3 yields 0.2 moles of CO2
1 mole of CO2 occupies 22.4 L
0.2 moles of CO2 occupies 0.2 × 22.4 = 4.48 L at STP
Hence;
V1=4.48 L
T1 = 273 K
P1= 760 mmHg
T2 = 27°C + 273 = 300 K
P2 = 760 mmHg
V2 =
P1V1/T1 = P2V2/T2
P1V1T2 = P2V2T1
V2 = P1V1T2/P2T1
V2 = 760 × 4.48 × 300/760 × 273
V2= 4.9 L
The limiting reactant is the reactant that determines the amount of product formed in a reaction. When the limiting reactant is exhausted, the reaction stops.
Determine the theoretical yield and the percent yield if 21.8 g of K2CO3 is produced from reacting 27.9 g KO2 with 57.0 g CO2. The molar mass of KO2
Answer:
26.9 g
81%
Explanation:
The equation of the reaction is;
4 KO2(s) + 2 CO2(g) → 3 O2(g) + 2 K2CO3(s)
Number of moles of KO2= 27.9g/71.1 g/mol = 0.39 moles
4 moles of KO2 yields 2 moles of K2CO3
0.39 moles of KO2 yields 0.39 × 2/4 = 0.195 moles of K2CO3
Number of moles of CO2 = 57g/ 44.01 g/mol = 1.295 moles
2 moles of CO2 yields 2 moles of K2CO3
1.295 moles of CO2 yields 1.295 × 2/2 = 1.295 moles of K2CO3
Hence the limiting reactant is KO2
Theoretical yield = 0.195 moles of K2CO3 × 138.205 g/mol = 26.9 g
Percent yield = actual yield/theoretical yield × 100
Percent yield = 21.8/26.9 × 100
Percent yield = 81%