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water from a town is suspected to contain chloride ions but not sulphate ions . describe how the presence of the chloride ions in the water can be shown
Answer:
See Explanation
Explanation:
The presence of chloride ions in water can be established by adding dilute trioxonitrate V acid to a sample of the water in drops followed by aqueous silver trioxonitrate V.
If a white precipitate is formed, which is soluble in excess aqueous ammonia solution, then the presence of chloride ion in the water sample is ultimately confirmed.
number of atoms per unit cell in face centred cube is
Answer: 4 atoms is the answer. I hope it helped you.
Explanation:
When 86.5 g of calcium chlorate decomposes into calcium chloride and oxygen, how many grams of oxygen are produced? Ca(ClO3)2 → CaCl2 + O2
Answer:
40.1 g
Explanation:
The balanced equation is:
Ca(ClO₃)₂ → CaCl₂ + 3O₂First we convert 86.5 g of calcium chlorate into moles, using its molar mass:
86.5 g Ca(ClO₃)₂ ÷ 206.98 g/mol = 0.418 mol Ca(ClO₃)₂Then we convert Ca(ClO₃)₂ moles into O₂ moles, using the stoichiometric coefficients of the balanced reaction:
0.418 mol Ca(ClO₃)₂ * [tex]\frac{3molO_2}{1molCa(ClO_3)_2}[/tex] = 1.254 mol O₂Finally we convert O₂ moles into grams:
1.25 mol O₂ * 32 g/mol = 40.1 g O₂You are given a bottle of NaOH of an unknown concentration. You are tasked with determining the concentration of this solution. You weigh out 0.3175 g of KHP (MW = 204.2 g/mol) and dissolve it in 40 mL of water. You add phenolphthalein to the solution as an indicator. You preform your titration and determine that it requires 19.45 mL of the unknown NaOH solution to reach the endpoint. From this information, calculate the concentration of the unknown solution.
Answer:
0.07975 M NaOH
Explanation:
First determine the molarity of your acid, KHP. Convert grams to moles using the MW given and then divide by the volume of water.
0.3175 g KHP • (1 mol KHP / 204.2 g KHP) = 0.001555 mol KHP
0.001555 mol KHP / 0.040 L = 0.03888 M KHP
The reaction between KHP and NaOH is one-to-one, so you can just use M1V1 = M2V2 to solve for M2 (the molarity of NaOH).
M1 = 0.03888 M KHP
V1 = 40 mL
M2 = ? M NaOH
V2 = 19.45 mL NaOH
(0.03888 M KHP)(40 mL) = M2(19.5 mL NaOH)
M2 = 0.07975 M NaOH
c) If 21.0 g of potassium reacts with 62.5 g of barium nitride, what mass of potassium nitride will be produced?
Explanation:
21.0 g of potassium reacts with 62.5 g of barium nitride, what mass of potassium nitride will be produced
If I contain 2 moles of gas in a container with a volume of 30 liters and at a temperature of 337 K, what is the pressure inside the container?
Answer:
1.84
Explanation: just input the value into the formula pv=nrt
p*30=2*0.08206*337 then divide both sides by 30 and get 1.84
Direction: Write true if the statement is correct and false if it is in correct.
1. Gravity cause all objects to fall at the same rate of speed as there is no air
resistance.
True. 1.) Gravity cause all objects to fall at the same rate of speed as there is no air
resistance.
Explanation:In fact, gravity works independently of mass. This means that all objects should fall at the same rate.
If there is no air resistance, or the same amount of air resistance, then objects of the same mass will fall at the same rate.
#CarryOnLearningwhat is the volume in liters at 422K if n and P does not change?
Answer:
0.75 L
Explanation:
V1/T1 = V2/T2
V1 = 0.520 L
T1 = 18 C = 291 K (make sure to convert to Kelvin by adding 273 to the Celsius temperature)
V2 = ?
T2 = 422 K
Solve the equation for V2
V2 = V1T2/T1
V2 = (0.520 L)(422 K) / (291 K) = 0.754 L ≈ 0.75 L (since it says to only give two significant figures)
Which of the following is TRUE about most gases?
1) They expand to completely fill their container.
2) They cannot be compressed.
3) All of their particles are the same size.
4) They have a fixed volume.
5) Their particles are very close together.
Explanation:
I think it is the first option
Answer:
1) They expand to completely fill their container. :)
Explanation:
Need help answering the last two, Its urgent please show how
During the reaction of 2,4-dinitrofluorobenzene with methoxide in methanol it was observed that it occurs at a significantly higher rate than the same reaction of 3,4-dinitrofluorobenzene. Explain the observation with a detailed mechanism and convincing structural arguments.
Answer:
Explanation:
your not so smart
how many mass extension of ocean animals have there been in the last 400-500million years
Answer:
Explanation:
Around 439 million years ago, 86% of life on Earth was wiped out. Scientists believe two major events resulted in this extinction: glaciation and falling sea levels. Some theories suggest that the Earth was covered in such a vast quantity of plants that they removed too much carbon dioxide from the air which drastically reduced the temperature. Falling sea levels were possibly a result of the Appalachian mountain range forming. The majority of the animal life lived in the ocean. Trilobites, brachiopods, and graptolites died off in large numbers but interestingly, this did not lead to any major species changes during the next era.
The half-life of I-37 is 8.07 days. If 25 grams are left after 40.35 days, how many grams were in the original sample?
Answer:
800 g
Explanation:
We can express the decay of I-37 using the formula:
Final Mass = Initial Mass * [tex]0.5^{\frac{Time}{Half-Life} }[/tex]We input the data:
25 g = Initial Mass * [tex]0.5^{(\frac{40.35}{8.07})}[/tex]And solve for Initial Mass:
25 g = Initial Mass * [tex]0.5^{5}[/tex]25 g = Initial Mass * 0.03125Initial Mass = 800 gMeaning that out 800 grams of I-37, only 25 will remain after 40.35 days.
0.500 mole of copper(II) sulfate contains
moles of O.
Answer:
2 mol
Explanation:
There are 4 mols of O per one sulfate so since there is only one sulfate you simply times 4 by .5 to get the number of mol
How was the position of planet Uranus predicted?
Upon studying the orbit of Uranus more closely, astronomers realized its orbit was being affected by the presence of another very large mass - so the hunt was on for another large planet. He sent his prediction to the Astronomer Royal, Sir George Airy, who passed it on to an 'observer'.
más inteligente o gracias por favor :)) <33 / brainliest or a thank you please :)) <33
The position of Uranus was predicted by determining the position of a larger mass ( Neptune ) exerting a gravitational push on Uranus
Uranus is the 7th planet in the galaxy it was initially discovered with the aid of a telescope by an astronomer whom initially thought it was a star.
The position of Uranus was predicted when an astronomer ( John Couch Adams ) and his colleague predicted the gravitational effect on Uranus from another larger mass ( Neptune ). they discovered the position of the larger mass affecting the orbit of Uranus and the position of this larger mass ( Neptune ) was used to predict the position of Uranus in the galaxy.
Hence we can conclude that the position of Uranus was predicted by determining the position of a larger mass ( Neptune ) exerting a gravitational push on Uranus
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What can be different between products and reactants in a balanced equation?
a) The total mass of products and reactants
b) The total moles of each element present in the reactants and in the products.
c) The number of molecules in the reactants and in the products
Answer:
b) The total moles of each element present in the reactants and in the products.
Explanation:
Hello there!
In this case, since the law of conservation of mass is used to realize that the mass, atoms and molecules of all the species involved in a chemical reaction must be the same at both reactants and products, we can see that a and c stand for those that must be equal; thus, we infer that the moles can be different as they stand for the amount of substance which is related to the mass via molar masses. Therefore, the answer would be b) The total moles of each element present in the reactants and in the products.
Regards!
Radioactive materials decay by a first-order process. The rate constant for the decay of an isotope whose half-life is 7.69 years is
Answer:
k = 0.0901 yrs⁻¹
Explanation:
1st order decay is defined by the equation A = A₀e^-k·t. If A = A₀/2 and t represents the 1st half-life of the isotope then ...
t(1/2) = ln2/k = 0.693/k => k = 0.693/t(1/2) = 0.693/7.69yrs = 0.0901 yrs⁻¹
How many atoms are in 6.78x1024 molecules of oxygen gas? PLEASE HELP WILL marK braNLIes
Which trend is observed as the first four elements in Group 17 on the Periodic Table are considered in order of increasing atomic number?
1. Electronegativity decreases
2. First ionization energy increases
3. The number of valence electrons increases
4. The number of electron shells decreases
What is the molarity of a solution made by adding :1.565 moles of PbN03 to 500 mL
Answer:
This question is a bit vague. We're not told if 500ml is the volume of the solution and additional info is not given to calculate the volume of pbNo3 being added.
If you solve with 500ml as the volume of solution ... You'll have the answer below.
Molarity=moles of solutes/Volume of solvent(in litres)
moles of solute given=1.565moles
Volume = 500ml. There's 1000ml to a litre. Dividing by 1000ml to convert to Litres... You have 0.5L
Molarity = 1.565/0.5
=3.13M
What is the iupac name for the compound shown?
Answer:Propanone is the IUPAC name for acetone, and butanone is the name for ethyl methyl ketone.
Explanation:
Warm air ___________________ and cold air __________________.
PLZ ILL GIVE BRAINLIEST!!!
Answer:
warm air rises and cold air decreases
Explanation:
cold: The absorbed energy moves and expands the molecules in the air, thus reducing the air density
hot: Hot air increases because it expands when you heat air.
Answer:
warm air rises and cold air decreases
Explanation:
cold: The absorbed energy moves and expands the molecules in the air, thus reducing the air density
hot: Hot air increases because it expands when you heat air.
15 The Following statement describes which body system? It also produces blood cells, and stores calcium. It regulates endocrine as well. This specific system uses all bones & joints in your body. A. The Lymphatic System B.The Muscular System C.The Reproductive System D.The Skeletal System
A sample of hydrogen takes up 34.0 dm3 of space when it is under 500.0 kPa of pressure. When the pressure is changed to 340.0 kPa, what is the new volume? dm3 H2
Answer:
50 dm³
Explanation:
Assuming constant temperature, we can solve this problem using Boyle's law, which states:
P₁V₁=P₂V₂Where in this case:
P₁ = 500.0 kPaV₁ = 34.0 dm³P₂ = 340.0 kPaV₂ = ?We input the data:
500.0 kPa * 34.0 dm³ = 340.0 kPa * V₂And solve for V₂:
V₂ = 50.0 dm³Thus the answer is 50.0 dm³ H₂.
What phase will you see one week after
Answer:
yes.
Explanation:
Hotel: trivago
What product(s) would be formed when these are the reactants? BaF2 + Cl2
How would the addition of protons affect the concentration of CH3COOH? How would the addition of OH– affect the amount of CH3COOH present? How would the addition of CH3COO– affect the concentration of protons? What would happen to [H+] if [CH3COOH] were increased?
Answer:
1) increase concentration
2) decrease the amount
3) decrease the concentration
4) it would increase
Explanation: edge 2021
Answer:
1) increase concentration
2) decrease the amount
3) decrease the concentration
4) it would increase
Explanation:
2.0 M H2SO4 solution.calculate the pH
Answer:
-.30
Explanation:
H2SO4/sulfuric acid/dihydrogen sulfate is a strong acid, meaning that it easily releases an H+. You have to be careful with this problem, however, as H2SO4 is really only a strong acid for one of its hydrogens. In other words, after it becomes HSO4- upon releasing an H+, it is no longer a strong acid and therefore should not be factored into our calculation.
Now, moving onto the calculation, there are two key things we need to carry it out. First is the pH equation. pH = -log [H+]. And second is the concentration of H2SO4, which is equivalent to the concentration of that H+ released: 2.0 M. Simply plug in your values.
pH = -log [2.0].
pH = -.30
Determine whether each described process is endothermic or exothermic.
a. Ice melts into liquid water
b. A process with a calculated positive q.
c. Wood burns in a fireplace.
d. A process with a calculated negative q.
e. Acid and base are mixed, making test tube feel hot.
f. Solid dissolves into solution, making ice pack feel cold
Answer:
Ice melts into liquid water- endothermic
A process with a calculated positive q - endothermic
Wood burns in a fireplace - exothermic
A process with a calculated negative q - exothermic
Acid and base are mixed, making test tube feel hot - exothermic
Solid dissolves into solution, making ice pack feel cold - endothermic
Explanation:
An endothermic process is one in which heat is absorbed from the surroundings. The absorption of heat means that heat is removed from the surroundings hence the surroundings feel cool. When heat is absorbed, q is positive.
An exothermic process is one in which heat is released to the surroundings. The evolution of heat means that heat is released into the surroundings hence the surroundings feel hot . When heat is evolved, q is negative.