Answer:
Researchers gather empirical evidence through experimentation or observation. Empirical evidence is information acquired by observation or experimentation. Scientists record and analyze this data
Answer: chemist
Explanation:
200ml hard water was boiled with 100ml N/50 Na2CO3 reagent. After boilingg the volume was again made to 200mand the solution filtered. 25ml of this filtrate required 8.2ml of N/50 HCl for neutralisation
Answer:
Here is the full question:
200ml hard water was boiled with 100ml N/50 Na2CO3 reagent. After boilingg the volume was again made to 200mand the solution filtered. 25ml of this filtrate required 8.2ml of N/50 HCl for neutralisation.
Calculate the permanent hardness in ppm.
Explanation:
Remember that the hard water was boiled with 100ml N/50 Na2CO3 reagent. Therefore, the milliequivalent of carbonate ion in 100 ml of N/50 Na2CO3 solution is given as 100 × [tex]\frac{1}{50}[/tex] = 2
The solution was made of 200 ml and 25 ml of the filtrate was neutralised with 8.2 ml N/50 HCl.
The milliequivalent of carbonate ions remaining in the filtrate is [tex]\frac{200}{25}[/tex] × 8.2 × [tex]\frac{1}{50}[/tex] = 1.3 milliequivalent
To get the milliequivalent of carbonate ion precipitated, we need to subtract the milliequivalent of the two carbonate ions. This will give us
2 − 1.3 = 0.7g
The amount of CaCO3 present in 200 ml water = 0.7 × 50 = 35g
Permanent hardness = [tex]\frac{35}{200}[/tex] × 1000 = 175 ppm.
Permanent hardness of water after boiling is 175ppm.
What is hardness of water?Hardness of water is of two types, one those will cam be removed by boiling is known as temporary hardness and which can not be removed by boiling is known as permanent hardness.
Given that hard water is heated with = 100mL N/50 Na₂CO₃.
Milliequivalent of carbonate ion in 100ml of N/50 Na₂CO₃ = 100×1/50=2
The milliequivalent of carbonate ions remaining in the filtrate is 200/25× 8.2 × 1/50 = 1.3 milliequivalent
Milliequivalent of carbonate ion precipitated = 2 - 1.3 = 0.7g
The amount of CaCO₃ present in 200 ml water = 0.7 × 50 = 35g
Permanent hardness will be calculated as:
P.H. = 35/200 × 1000 = 175ppm.
Hence, permanent hardness of water is 175ppm.
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What volume of 1.25 M sodium hydroxide (NaOH) solution can be prepared using 60.0 g of sodium hydroxide? (The mass of one mole of NaOH is 40.0 g.)
0.667 L
0.833 L
1.20 L
1.88L
Answer:
The answer is
1.20 LExplanation:
Since the concentration , mass and molar mass of NaOH has been given we use the formula
[tex]C = \frac{m}{M \times v} [/tex]To find the volume
where
C is the concentration
m is the mass
M is the molar mass
v is the volume
Making volume the subject we have
[tex]v = \frac{m}{C \times M} [/tex]From the question
C = 1.25 M
m = 60 g
M = 40.0 g/mol
Substitute the values into the above formula and solve for the volume
We have
[tex]v = \frac{60}{1.25 \times 40} \\ v = \frac{60}{50} \\ v = \frac{6}{5} [/tex]We have the final answer as
Volume = 1.20 LHope this helps you
What is the minimum mass of magnetite (Fe,O2), a iron ore, from which 120. g of pure iron could be extracted? Be sure your answer has a unit symbol, if necessary, and is rounded to 3 significant digits.
Answer:
166 g
Explanation:
Step 1: Write the reaction for the obtaining of Fe from magnetite
Fe₃O₄ ⇒ 3 Fe + 2 O₂
Step 2: Calculate the moles corresponding to 120 g of Fe
The molar mass of Fe is 55.85 g/mol.
120 g × (1 mol/55.85 g) = 2.15 mol
Step 3: Calculate the moles of Fe₃O₄ required to produce 2.15 moles of Fe
The molar ratio of Fe₃O₄ to Fe is 1:3. The moles of Fe₃O₄ required are 1/3 × 2.15 mol = 0.717 mol
Step 4: Calculate the mass corresponding to 0.717 moles of Fe₃O₄
The molar mass of Fe₃O₄ is 231.53 g/mol.
0.717 mol × 231.53 g/mol = 166 g
A racecar burns gasoline to power its engine. As the car is racing around a track, what energy is involved in the system? Check all that apply. mechanical energy chemical energy thermal energy electromagnetic energy
Answer:
The internal combustion engine in the car converts the potential chemical energy in gasoline and oxygen into thermal energy which is transformed into the mechanical energy that accelerates the vehicle (increasing its kinetic energy) by causing the pressure and performing the work on the pistons.
Answer:
A, B, and C are the correct options.
Explanation:
I just did it on Edge2023
What is science in 5 sentences
Answer:
Science is both boon and curse for living beings.
Science is the action to find out any fact regarding the natural world.
Science gives accurate facts, formulas, laws and theories.
Science has many major fields like chemistry, physics, biology etc.
Science is valued by society because the application of scientific knowledge helps to satisfy many basic human needs and improve living standards.
Draw the structural formula for 3-ethyl-3-methyl-1-pentyne. Click the "draw structure" button to launch the drawing utility.
Answer:
See attached picture.
Explanation:
Hello,
In this case, for the given name, you can verify the structure on the attached picture, wherein you can see verify the presence of both the ethyl and methyl radicals at the third carbon as well as the triple bond at the first carbon.
Best regards.
After mixing an excess PbCl2 with a fixed amount of water, it is found that the equilibrium concentration of Pb2 is
Answer:
Ksp = 8.8x10⁻⁵
Explanation:
Full question is:
After mixing an excess PbCl2 with a fixed amount of water, it is found that the equilibrium concentration of Pb2+ is 2.8 × 10–2 M. What is Ksp for PbCl2?
When an excess of PbCl₂ is added to water, Pb²⁺ and Cl⁻ ions are produced following Ksp equilibrium:
PbCl₂(s) ⇄ Pb²⁺ + 2Cl⁻
Ksp = [Pb²⁺] [Cl⁻]²
If an excess of PbCl₂ was added, an amount of Pb²⁺ is produced (X) and twice Pb²⁺ is produced as Cl⁻ (2X):
Ksp = [X] [2X]²
Ksp = 4X³
As X is the amount of Pb²⁺ = 2.8x10⁻²M:
Ksp = 4(2.8x10⁻²)³
Ksp = 8.8x10⁻⁵What is the molecular formula and chemical name of the compound? Examine the image. The letters Si in the center with four lines connecting it to 4 Fs, 1 in each direction.
Answer:
molecular formula is "SiF4" and compound name is "silicon tetrafluoride"
Explanation:
Which of these statements correctly compares probeware (such as an electronic temperature probe) to traditional analog tools (such as a liquid-based thermometer)? Measurements by traditional analog tools are good to a larger number of significant figures. Measurements by traditional analog tools are less prone to experimental error. Probeware is typically very difficult to transport. Probeware is useful for obtaining many measurements in rapid succession.
The correct answer is D. Probeware is useful for obtaining many measurements in rapid succession.
Explanation:
Probeware refers to specialized equipment and programs that collect and analyze data. Indeed, Probeware integrates tools to register information such as distance or temperature with software. This complex system is useful to record and analyze a lot of data or measurements, which is not possible with analog tools. Moreover, due to the integration of software, multiple measurements can be recorded and analyzed in a short time, which is known as rapid succession. According to this, one difference between Probeware and analog tools is that "Probeware is useful for obtaining many measurements in rapid succession."
Answer:
Probeware is useful for obtaining many measurements in rapid succession.
What type of elements is on the right side of a Periodic Table?
What type is on the left?
Answer:
the right side of the periodic table are metals while the left side are non metals (with the exception of hydrogen)
The estimated costs for remodelling the interior of an apartment are: three 1-gallon cans of paint at $13.69 each, two paint brushes at $9.53 each, and $135 for a helper. The total estimated cost with the appropriate significant figures is $
Answer:
$195
Explanation:
Step 1: Given data
Cost of a 1-gallon can of paint (cC): $13.69Number of 1-gallon cans of paint (nC): 3Cost of a paint brush (cB): $9.53Number of paint brushes (nB): 2Cost of a helper (cH): $135Number of helpers (nH): 1Step 2: Calculate the total estimated cost for remodelling the interior of an apartment
We will use the following expression.
C = cC × nC + cB × nB + cH × nH
C = $13.69 × 3 + $9.53 × 2 + $135 × 1
C = $195
How many grams of a 14.0% (w/w) sugar solution contain 62.5
of sugar?
Answer:
[tex]m_{solution}=446.4g[/tex]
Explanation:
Hello,
In this case, by-mass percent is computed in terms of the mass of the solute and the mass of the solvent as shown below:
[tex]\% m=\frac{m_{solute}}{m_{solution}} *100\%[/tex]
Thus, solving for the mass of the solution, we obtain:
[tex]\frac{x}{y} m_{solution}=\frac{m_{solute}}{\% m}*100\%\\ \\m_{solution}=\frac{62.5g}{14.0\%}*100\% \\\\m_{solution}=446.4g[/tex]
Regards.
Spongebob was trying to make Krabby Patties that weighed 12oz. He made 4 Krabby Patties. They all had the following weights: 12.12oz; 11.9oz; 12.2oz; 12.1oz. Is this an example of Accuracy? Precision? Both? Neither?
Answer:
Yes, the 4 Krabby patties are an example of high precision.
Explanation:
Precision is the closeness of the values obtained by applying them to the same parameter. To calculate the precision, the closeness of each of the values with the mean must be determined, all the values will be taken by subtracting the mean and the values will be taken into account to know which are the most accurate.
(12.12 + 11.9 + 12.2 + 12. 1) / 4 = 12.08
12.12 - 12.8 = 0.04
11.9 - 12.08 = - 0. 18
12.2 - 12.08 = 0.12
12.1 - 12.08 = 0.02
The most accurate precision is that of the fourth Krabby Pattie and the least precise is that of the second.
Explanation:
Step 1: Determine what precision and accuracy is
According to online, "precision is how close measure values are to each other, basically how many decimal places are at the end of a given measurement. Precision does matter. Accuracy is how close a measure value is to the true value. Accuracy matters too, but it's best when measurements are both precise and accurate."
Step 2: Determine which are displayed in this problem
We can see that most of these weight are really close to the original weight which means that the accuracy is pretty high. This means that our weights are fairly close to the original predicated amount.
We can also see that our precision is somewhat decent because most of the numbers bunch up around each other. Precision and accuracy don't have to occur at the same time. For example, a precise collection can be 15, 15.01, 14.99. Although they are far away from the original point, they are bunched up together giving a high precision.
What volume (cm 3 ) would 9.0 grams of aluminum occupy? Density is 2.7 g/cm 3 . Show your work
Answer:
3.3 cm³
Explanation:
Use the density formula, d = m/v, to solve for the volume:
2.7 = 9.0/v
2.7v = 9.0
v = 3.3 cm³
how to calculate average mass in grams?
Explanation:
hope these help you answer
explain why the neutralization reaction of a strong base and weak acid gives a weakly basic solution
Answer:
when an acid react with a base, salt and water is produced. It is because the nature of salt formed determines whether the solution is neutral, acidic or basic
Hope this helps :)
How many electrons does each lithium atom provide to the voltaic cell? Question 6 options: A) 2 B) 1 C) 3 D) 4
Answer:
B) 1
Explanation:
Lithium is a univalent element, univalent means that it has only one valence electron. If this is true, then lithium can only provide this one valence electron in a voltaic cell.
From the foregoing, each lithium atom can only provide one valence electron in the voltaic cell.
Answer:
B) 1
Explanation:
I got it in class!
Hope this Helps!! :))
how many pi bonds does a triple bond has
Answer:
A triple bond have two pi bonds.
Explanation:
This is an alkaline that contains one sigma bond and two pi bonds.
Hope my answer helps.
Answer:
Two
Explanation:
Liquid methanol (CH3OH) reacts with oxygen gas to form carbon dioxide gas and water vapor. Express your answer as a chemical equation. Identify all of the phases in your answer.
Answer:
[tex]2CH_3OH_{(l)} + 3O_2_{(g)} --> 2CO_2_{(g)} + 4H_2O_{(g)}[/tex]
Explanation:
The reaction between methanol and oxygen can be expressed as an equation below:
[tex]CH_3OH + O_2 --> CO_2 + H_2O_[/tex]
However, the equation is not balanced as the number of the molecule of each atom on the right-hand side and the left-hand side is not the same. The balanced equation showing the phases of all the reactants and products is as below:
[tex]2CH_3OH_{(l)} + 3O_2_{(g)} --> 2CO_2_{(g)} + 4H_2O_{(g)}[/tex]
Two molecules of liquid methanol react with three molecules of oxygen gas to give 2 molecules of carbon dioxide gas and four molecules of water vapor.
Calculate the solubility of BaCrO4 in water at . You'll find data in the ALEKS Data tab. Round your answer to significant digits.
Answer:
1.08 × 10⁻⁵ M
Explanation:
Calculate the solubility of BaCrO₄ in water at 25°C. You'll find data in the ALEKS Data tab. Round your answer to 3 significant digits.
Step 1: Write the reaction for the solution of BaCrO₄
BaCrO₄(s) ⇄ Ba²⁺(aq) + CrO₄²⁻(aq)
Step 2: Make an ICE chart
We can relate the molar solubity (S) with the solubility product constant (Ksp) using an ICE chart. The Ksp for BaCrO₄ is 1.17 × 10⁻¹⁰.
BaCrO₄(s) ⇄ Ba²⁺(aq) + CrO₄²⁻(aq)
I 0 0
C +S +S
E S S
The solubility product constant is:
Ksp = 1.17 × 10⁻¹⁰ = [Ba²⁺] [CrO₄²⁻] = S²
S = √1.17 × 10⁻¹⁰ = 1.08 × 10⁻⁵ M
Which are different forms of an element that have different numbers of neutrons?
The number of neutrons is variable, resulting in isotopes, which are different forms of the same atom that vary only in the number of neutrons they possess. Together, the number of protons and the number of neutrons determine an element's mass number.
tbh google
hope it helps
Explanation:
The atoms of a chemical element can exist in different types. These are called isotopes. They have the same number of protons (and electrons), but different numbers of neutrons.
For the following reaction,increasing the pressure will cause the equilibrium to ________.
2SO2 (g) + O2 (g)_ 2 SO3 (g) +heat
A) remain unchanged, but the reaction mixture will getcooler
B) shift to the right, towards products
C) shift to the left, towards reactants
D) remain unchanged, but the reaction mixture will getwarmer
E) Pressure has no effect on equilibrium.
For the given reaction increasing the pressure will cause the equilibrium to shift to the left, towards reactants.
What is equilibrium law?According to this law on applying extrenal stress on the equilibrium state of any reaction then it will shift to that side where effect of the stress getting low.
Given chemical reaction is:
2SO₂(g) + O₂(g) → 2SO₃(g) + heat
In the reaction heat is also produced in the forward direction and from the ideal gas equation PV=nRT it is clear that pressure is directly proportional to the temperature. So when we increasing the presssure then temperature will also increase as a result of increase in heat. So minimize this effect reaction will shift to the left side.
Remain unchanged with cooler and warmer condition is impossible.will not shift to right side as it also increases pressure.Hence reaction will shift to the left side of the equilibrium.
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How do you determine a number of each particle?
Answer:
Search Results
Featured snippet from the web
To calculate the numbers of subatomic particles in an atom, use its atomic number and mass number:
number of protons = atomic number.
number of electrons = atomic number.
number of neutrons = mass number - atomic number.
Explanation:
6) Select an element from the periodic table that interests you. Look it up on the internet and write down some
interesting facts about it. |
Answer:
Copper (cu)
Explanation:Copper (Cu), chemical element, a reddish, extremely ductile metal of Group 11 (Ib) of the periodic table that is an unusually good conductor of electricity and heat. Copper is found in the free metallic state in nature. This native copper was first used (c. 8000 BCE) as a substitute for stone by Neolithic (New Stone Age) humans.
. Metallurgy dawned in Mesopotamia as copper was cast to shape in molds (c. 4000 BCE), was reduced to metal from ores with fire and charcoal, and was intentionally alloyed with tin as bronze
atomic number 29
atomic weight 63.546
melting point 1,083 °C (1,981 °F)
boiling point 2,567 °C (4,653 °F)
density 8.96 at 20 °C (68 °F)
valence 1, 2
electron configuration 2-8-18-1 or (Ar)3d104s1
Copper is one of the most ductile metals, not especially strong or hard. Strength and hardness are appreciably increased by cold-working because of the formation of elongated crystals of the same face-centred cubic structure that is present in the softer annealed copper.
Copper (Cu), chemical element, a reddish, extremely ductile metal of Group 11 (Ib) of the periodic table that is an unusually good conductor of electricity and heat. Copper is found in the free metallic state in nature. This native copper was first used (c. 8000 BCE) as a substitute for stone by Neolithic (New Stone Age) humans. Metallurgy dawned in Mesopotamia as copper was cast to shape in molds (c. 4000 BCE), was reduced to metal from ores with fire and charcoal, and was intentionally alloyed with tin as bronze
atomic number 29
atomic weight 63.546
melting point 1,083 °C (1,981 °F)
boiling point 2,567 °C (4,653 °F)
density 8.96 at 20 °C (68 °F)
valence 1, 2
electron configuration 2-8-18-1 or (Ar)3d104s1
Copper is one of the most ductile metals, not especially strong or hard. Strength and hardness are appreciably increased by cold-working because of the formation of elongated crystals of the same face-centred cubic structure that is present in the softer annealed copper.
30.0 mL of pure water at 282 K is mixed with 50.0 mL of pure water at 343 K. What is the final temperature of the mixture
The final temperature of the mixture will be "305.6 K".
Heat and temperatureAccording to the question,
Mass of water, m₁ = 30.0 mL or,
= 30.0 mL × 1 g/mL
= 30.0 g
and,
m₂ = 50.0 mL × 1 g/mL
= 50.0 g
Specific heat of water = 4.18 J/g°C
We know the relation,
→ Heat lost + Heat gained = 0
By substituting the values,
30.0 × 4.18 (T - 282) + 50.0 × 4.18 (T - 320) = 0
30.0 × 4.18T - 1178.76 + 50.0 × 4.18T - 1337.6 = 0
hence,
The final temperature will be:
T = 305.6 K
Thus the answer above is appropriate.
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It is relatively easy to change the temperature of a substance that:_______
a. is an insulator.
b. has a low specific heat capacity
c. has a high specific heat capacity.
d. is brittle. e is very massive
Answer:
b. has a low specific heat capacity.
Explanation:
Hello,
In this case, since the specific heat is defined as the heat required to increase or decrease 1 degree Celsius 1 gram or mole of a specific substance, we infer that the lower the specific heat, the less energy will be needed for such increase or decrease, therefore, it turns out easier to modify the temperature in a substance that b. has a low specific heat capacity.
Best regards.
Which makes up an ecosystem?
A. A community of organisms and nonliving factors in their habitats
B. Several species of organisms that are similar in appearance
C. A group of species and the plants that they interact with
D. Multiple populations of animals and the plants in their environment
Olivia noticed that the pH of her garden soil decreased after it rained. Did her garden soil become more acidic or less acidic
Answer:
The garden soil become more acidic.
Explanation:
The pH is defined as -log [H⁺]. An acidic solution contains an important amount of [H⁺]. When the pH increases, H⁺ decreases doing the solution more basic. In the other way, an increasing in H⁺ concentration decreases the pH doing the solution more acidic.
The pH of the garden soil of Olivia decreases after it rained. As pH decreases, [H⁺] increases become the garden soil more acidic.
g How many grams of beryllium are needed to produce "11.5" g of hydrogen gas?Be(s) + 2H 2 O(l) → Be(OH) 2 (aq) + H 2 (g)
Answer:
[tex]m_{Be}=51.3gBe[/tex]
Explanation:
Hello,
In this case, with the given chemical reaction:
[tex]Be(s) + 2H_2 O(l) \rightarrow Be(OH)_ 2 (aq) + H _2 (g)[/tex]
We can notice a 1:1 mole ratio between hydrogen gas and beryllium metal, therefore, beryllium requirement is computed as shown below:
[tex]m_{Be}=11.5gH_2*\frac{1molH_2}{2.02gH_2} *\frac{1molBe}{1molH_2} *\frac{9.01gBe}{1molBe}\\ \\m_{Be}=51.3gBe[/tex]
Regards.
Convert a speed of 259 cm/s to units of inches per minute. Also, show the unit analysis by dragging components into the unit‑factor slots.
Answer:
[tex]6118.11\frac{in}{min}[/tex]
Explanation:
Hello,
In this case, by knowing that 1 inch equals 2.54 cm and 60 seconds equals 1 min, the resulting value results:
[tex]=259\frac{cm}{s}*\frac{1in}{2.54cm}*\frac{60s}{1min}\\ \\=6118.11\frac{in}{min}[/tex]
Best regards.