Answer:
Sample A is a mixture
Sample B is a mixture
Explanation:
If we look at sample A, we can easily notice that the sample powder was found to float while some of it settled below. This means that the sample is not entirely homogeneous. A homogeneous sample always constitutes a single phase in solution. Also, the dried mass yields 50.1 g while only 50.0 g of the yellow cube was ground and dissolved. This shows that the original cube is not pure. A sample that is not entirely homogeneous is not pure.
Secondly, the fact that the density of liquid that remains in the flask is different from the density of the sample initially measured indicates that the original sample B is a mixture of substances.
If a substance has a density of 1.345g / mL , how many grams would the substance weigh if the sample has a volume of 22.1 ml?
Answer:
Mass of substance = 29.7245 gram
Explanation:
Given:
Density of substance = 1.345 g / ml
Volume of substance = 22.1 ml
Find:
Mass of substance
Computation:
Mass = Density x Volume
Mass of substance = Density of substance x Volume of substance
Mass of substance = 1.345 x 22.1
Mass of substance = 29.7245 gram
1. The grains are separated from stalks by winnowing. (True/False
many types of animals have internal skeletons a large part of these animals masses located in them bones as an animal grows its skeleton grows a growing animal must increase the size of its bones to do this animal needs lots of calcium an element important to do structure of Bones how can a growing animal get calcium to make new bones tissue? A-by removing calcium from the air B- by consuming food that contains Calcium C- by making calcium from other elements D- by removing calcium from the bones
Answer: b- by consuming food that contains calcium
Explanation:
Can someone help me pls I don’t have time Time is almost ran out pls help
Answer:
Can you get a closer picture, then I can help! It looks like it says something on rain, hail and something else. I cant see it though! :)
Explanation:
Metal vapor deposition is a process used to deposit a very thin layer of metal on a target substrate. A researcher puts a glass slide in the metal vapor deposition chamber and coats the slide with titanium. After deposition, the glass slide had increased in mass by 2.05 milligrams. Approximately how many titanium atoms were deposited on the glass slide
Answer:
2.58 * 10^19 atoms of titanium
Explanation:
Mass of Titanium ions deposited = 2.05 * 10^-3 g of Ti
Molar mass of titanium = 47.87 g/mol
Number of moles of Titanium deposited = 2.05 * 10^-3 g/47.87 g/mol = 4.28 * 10^-5 moles
Number of atoms of titanium deposited = number of moles of titanium * Avogadro's number
Number of atoms of titanium deposited =4.28 * 10^-5 moles * 6.02 * 10^23 = 2.58 * 10^19 atoms of titanium
Please help me with these 3 questions with will be giving out brainiest
Answer: All of them are true
What is the mole ratio needed to determine the mass of phosphorus trifluoride produced from the reaction of 120 g of phosphorus with excess fluorine?
Answer:
[tex]\frac{4molPF_3}{1molP_4}[/tex]
Explanation:
Hello
In this case, given the reaction:
[tex]P_4(s)+6F_2(g)\rightarrow 4PF_3(g)[/tex]
It means that since the coefficients preceding phosphorous and phosphorous trifluoride are 1 and 4, the correct mole ratio should be:
[tex]\frac{4molPF_3}{1molP_4}[/tex]
Because given the mass of phosphorous it is convenient to convert it to moles and then cancel it out with the moles on bottom of the mole ratio.
Bes regards!
For ionic bonding, the net potential energy between two adjacent ions, EN, may be represented by the sum of Equations 2.8 and 2.9 from the text; that is, The binding energy 0 represents that point where EN is minimized. Derive an expression for the bonding energy in terms of the parameters A, B, and n. (Hint: first differentiate and derive an expression for r0, the equilibrium interionic spacing, in terms of A, B, and n. r
Answer:
- [ A/[A/nB]^1/1-n + B/ [A/nB]^n/1-n].
Explanation:
The mathematical representation for the net potential energy as described in the Question above is given below as;
En = -A/r + B/r^n.
Therefore, let's call the equation above equation (1). Hence, there is the need to differentiate equation (1) above wrt r.
(NB: wrt = with respect to)
Thus, [dEn/ dr] = 0. -------------------------(2).
d [ - A/r + B/r^n]/ dr = 0. -------------------(3).
A/r^2 - nB/r^n+1 = 0 ------------------------(4).
r^2/r^n+1 = A/nB ----------------------------(5).
r^1-n = A/nB -----------------------------------(6).
(1 - n )ln r= ln A/nB ------------------------(7)
ln r = 1/1 - n ln [A/nB] ---------------------(8).
r = e^ln(A/nB)^1/1-n ----------------------(9).
r = [A/nB]^1/1-n. ---------------------------(10).
Thus, put the value in (10) above that is r = [A/nB]^1/1-n into equation (1).
Hence, the bonding energy = - [ A/[A/nB]^1/1-n + B/ [A/nB]^n/1-n].
Which of the following lewis structures is correct?
нс
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a.
b. HH
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c.
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H
d.
Answer:
Hope this helps:
Explanation:
Correct H H Part C Sketch the reson.
Worth 100 points if able to help, please! (show work if possible)
Answer:The answer would be 2 sorry i cant show the work right now
Explanation:
Answer:
2
Explanation:
1 Srcl (aq) + 1 H,60,(aq) → 2 HCl(aq) + 1 Srso (s)
What is the mass of strontium chloride that reacts with 300.0 g of sulfuric
acid?
Answer:
Mass = 245.72 g
Explanation:
Given data:
Mass of SrCl₂ react = ?
Mass of H₂SO₄ = 300.0 g
Solution:
SrCl₂ + 2H₂SO₄ → 2HCl + Sr(HSO₄)₂
Number of moles of H₂SO₄:
Number of moles = mass/molar mass
Number of moles = 300.0 g/ 98.079 g/mol
Number of moles = 3.1 mol
Now we will compare the moles of SrCl₂ and H₂SO₄.
H₂SO₄ : SrCl₂
2 : 1
3.1 : 1/2×3.1 = 1.55 mol
Mass of SrCl₂:
Mass = number of moles × molar mass
Mass = 1.55 mol × 158.53 g/mol
Mass = 245.72 g
Calculate the volume of a box which is 125 cm long, 37 cm wide, and 68 cm high. Report your answer with correct significant figures in cubic centimeters. please use significant figures!
Calculate the volume of a box which is 423 cm long, 12 cm wide, and 25 cm high. have significant figures in cubic centimeters.
Suppose you are measuring the mass of a solid sample on a balance using a weigh boat. You record the data in a table. Mass of weigh boat 1.326 g Mass of weigh boat and sample 7.635 g What is the mass of the solid sample?
A graduated cylinder contains 10.00 mL water. A 14.74 g piece of aluminum is added to the water, and the volume rises to 15.46 mL. What is the density of the aluminum?
A 24.5 g sample of solution has a density of 0.768 g/mL. What is the sample volume (in mL)?
Answer:
1. Volume of box is 314500 cm³.
2. Volume of box 126900 cm³.
3. Mass of sample is 6.309 g.
4. Density of aluminum is 2.7 g/mL.
5. Volume of sample is 31.9 mL.
Explanation:
1. Determination of the volume of the box
Length (L) = 125 cm
Width (W) = 37 cm
Height (H) = 68 cm
Volume (V) =?
V = L × W × H
V = 125 × 37 × 68
V = 314500 cm³
2. Determination of the volume of the box
Length (L) = 423 cm
Width (W) = 12 cm
Height (H) = 25 cm
Volume (V) =?
V = L × W × H
V = 423 × 12 × 25
V = 126900 cm³
3. Determination of the mass of the sample.
Mass of weigh boat = 1.326 g
Mass of weigh boat + Sample = 7.635 g Mass of the sample =?
Mass of Sample = (Mass of weigh boat + Sample) – (Mass of weigh boat)
Mass of Sample = 7.635 – 1.326
Mass of Sample = 6.309 g
4. Determination of the density of aluminum.
Volume of water = 10 mL
Mass of aluminum = 14.74 g
Volume of water + aluminum = 15.46 mL
Density of aluminum =?
Next, we shall determine the volume of aluminum. This can be obtained as follow:
Volume of water = 10 mL
Volume of water + aluminum = 15.46 mL
Volume of aluminum =?
Volume of aluminum = (Volume of water + aluminum) – (Volume of water)
Volume of aluminum = 15.46 – 10
Volume of aluminum = 5.46 mL
Finally, we shall determine the density of aluminum. This can be obtained as follow:
Mass of aluminum = 14.74 g
Volume of aluminum = 5.46 mL
Density of aluminum =?
Density = mass / volume
Density of aluminum = 14.74 / 5.46
Density of aluminum = 2.7 g/mL
5. Determination of the volume of sample.
Mass of sample = 24.5 g
Density of sample = 0.768 g/mL.
Volume of sample =?
Density = mass / volume
0.768 = 24.5 / volume of sample
Cross multiply
0.768 × Volume of sample = 24.5
Divide both side by 0.768
Volume of sample = 24.5 / 0.768
Volume of sample = 31.9 mL.
Which statement best describes most tundra animals?
A. slender and short, so they can move quickly
B. hardly any fur or feathers because they are warm-blooded
C. stocky bodies covered with thick fur or feathers
D. most of their time is spent underground, so they are insulated
Answer:
C. stocky bodies covered with thick fur or feathers
Explanation:
Animals in the tundra generally have stocky bodies covered with thick fur or feathers.
A tundra is a very cold biome. In fact, it is the coldest of all the biomes found on the earth. This region is found in the Arctic and other parts of the world. It is treeless, very cold and has little to no precipitation all year round.
Animals here must be highly adapted to the cold all year round. They must possess a stocky body with added layer of fats so as to insulate them from losing heat. Their thick feathers and furs serves are great advantage for them also in conserving bodily heat. Examples of animals here are bears, foxes etcA 558 mg of a mixture of fluorene and benzoic acid was weighed out and subjected to an extraction and recrystallization. After this purification was completed the product crystals were dried and analyzed. The purification procedure produced 185 mg of fluorene and 144 mg of benzoic acid. Calculate the percent composition of this mixture.
Answer:
See explanation
Explanation:
Mass of mixture of fluorene and benzoic acid = 558 mg
Mass of pure fluorene after purification = 185 mg of fluorene
Mass of pure benzoic acid after purification = 144 mg of benzoic acid
Percentage of fluorene int he mixture = 185mg/558mg * 100 = 33.15 %
Percentage of benzoic acid in the mixture = 144mg/558mg * 100 = 25.81 %
Percentage of impurities = 100% - [33.15 + 25.81]
Percentage of impurities = 100 - 58.96
Percentage of impurities = 41.04 %
If Jim has a mass of 70 kg and is running at a rate of 6 m/s, what would his momentum be?
Answer:
p = 420 kg·m/s
Explanation:
i just looked up momentum calculator
There are 235.5 grams of Calcium chloride dissolved in 2.5 liters of solution. What is the molarity of
this solution?
Substance A dissolves in water. What can be said about substance A?
O It is unsaturated.
It is nonpolar.
It is saturated.
It is polar.
Answer:
It is polar.
Explanation:
Water is a polar solvent and it can only dissolve another solute or substance.
As a general rule of solubility "likes dissolves likes".
This implies that when a polar solvent is used, it will dissolve a polar solute.
Also, a non-polar solute will only dissolve in a non-polar solvent.
Water is an example of polar solute. Other solutes such as salt can dissolve in water because they are polar in nature. A non-polar solvent is oil.describe the difference beetween an extensive and intesive property
Extensive properties, such as mass and volume, depend on the amount of matter being measured. Intensive properties, such as density and color, do not depend on the amount of the substance present. Physical properties can be measured without changing a substance's chemical identity.
Cellular respiration is? (Single choice.)
A. a chemical reaction that converts energy from food molecules by way of oxygen into a usable energy called ATP.
B. a chemical reaction that converts carbon dioxide and water into glucose and oxygen.
C. a chemical reaction that converts that occurs only in animals.
D. a chemical reaction that occurs only in plants.
How many moles are present in 281 grams of arsenic
How many grams of MgO are produced from the complete reaction of 94.2 g Mg?
Answer:
157 g of MgO
Explanation:
the reaction:
2Mg + O2 ➡️ 2MgO
1) find the mol of Mg
mol = mass / molar mass
mass = 94.2 g
molar mass = 24
mol = 94.2 / 24
mol = 3.925 mol
2 mol = 3.925 moles
2) find mass of MgO
mass = mol × molar mass
mol = 3.925
molar mass = 24+16 = 40
mass = 3.925 × 40
= 157 g
Which is a result of the high surface tension of water?
A. Water droplets are round.
B. Water freezes from the top down.
C. Ionic compounds are soluble in water.
D. Oil and water separate into two layers.
Answer:
A
Explanation:
The temperature of 100 mL of a gas is increased from
20°C to 120°C while the pressure is held constant.
What is the new volume of the gas?
Answer:
V₂ = 134.11 mL
Explanation:
Given data:
Initial volume = 100 mL
Initial temperature = 20°C (20+273.15 K = 293.15 K)
Final temperature = 120°C(120+273.15 K = 393.15 K)
Final volume = ?
Solution:
The given problem will be solve through the Charles Law.
According to this law, The volume of given amount of a gas is directly proportional to its temperature at constant number of moles and pressure.
Mathematical expression:
V₁/T₁ = V₂/T₂
V₁ = Initial volume
T₁ = Initial temperature
V₂ = Final volume
T₂ = Final temperature
Now we will put the values in formula.
V₁/T₁ = V₂/T₂
V₂ = V₁T₂/T₁
V₂ = 100 mL × 393.15 K / 293.15 K
V₂ = 39315 mL.K / 293.15 K
V₂ = 134.11 mL
What is the mass of 5.07 mol N2?
(Answer)grams (3 SF)
Answer:
Mass, m = 141.96 kg
Explanation:
Given that,
Moles = 5.07
Molar mass of N₂ = 28 g/mol
We need to find the mass of 5.07 mol N₂.
We know that,
No of moles is equal to mass divided by molar mass i.e.
[tex]n=\dfrac{m}{M}[/tex]
Where
m is mass of 5.07 mol of N₂
So,
[tex]m=n\times M\\\\m=5.07\times 28\\\\m=141.96\ kg[/tex]
So, the required mass of 5.07 mol N₂ is 141.96 kg.
Is elemental copper a pure substance
Answer:
yes
Explanation:
copper is a pure substance in any form
How does mechanical weather affect rocks?
Mechanical weathering can cause rocks to melt.
Mechanical weathering can relocate rocks to different locations.
Mechanical weathering can cause rocks to break apart into sediments.
Mechanical weathering can change rocks into a different materials.
Answer:
C
Explanation:
Mechanical weathering, also called physical weathering and disaggregation, causes rocks to crumble. Water, in either liquid or solid form, is often a key agent of mechanical weathering. For instance, liquid water can seep into cracks and crevices in rock. ... It slowly widens the cracks and splits the rock
Convert 1020 mm Hg to atm
Answer:
1.34
Explanation:
WILL MARK BRAINLIEST
What is the next smallest classification group after Order? ________
What is the smallest classification group?________
which wave carris most energy
Answer:
Gamma Rays
Explanation:
Hope it helps!! :))
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Answer:
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Explanation:
A 3.25 L solution is prepared by dissolving 285 g of BaBr2 in water. Determine the molarity.
Answer:
0.295 mol/L
Explanation:
Given data:
Volume of solution = 3.25 L
Mass of BaBr₂ = 285 g
Molarity of solution = ?
Solution:
Molarity is used to describe the concentration of solution. It tells how many moles are dissolve in per litter of solution.
Formula:
Molarity = number of moles of solute / L of solution
Number of moles of solute:
Number of moles = mass/ molar mass
Molar mass of BaBr₂ = 297.1 g/mol
Number of moles = 285 g/ 297.1 g/mol
Number of moles= 0.959 mol
Molarity:
M = 0.959 mol / 3.25 L
M = 0.295 mol/L
