Explanation:
Ca(OH) is a base
pOH = -Log[OH]
[OH] = 0.05
pOH = -Log(0.05)
pOH = 1.3
pH + pOH = 14
pH = 14 - pOH
pH = 14 - 2
pH = 12.7
Question 2 Multiple Choice Worth 2 points)
(01.01 LC)
Which of the following is a characteristic of science?
O Reproducible by other scientists
The personal opinion of the scientist
Using vanable conditions for each test
O Including only the data that supports a hypothesis
Question 3 Multiple Choice Worth 2 points)
Answer:
Reproducible by other scientists
The personal opinion of the scientist
Using vanable conditions for each test
Explanation:
If 16.4 grams of calcium nitrate is heated as shown in the reaction:
2Ca(NO3)2 -> 2CaO + 4NO2 + O2.
Calculate the volume of nitrogen dioxide produced at STP.
Answer:
7.2
Explanation:
you first have to find the number of moles of nitrogen dioxide by using the number of moles for calcium nitrate and the mole to mole ratios
number of moles of calcium nitrate=mass/mm
=16.4/102
=0.16g/mol
then you use the mole to mole ratios
2 : 4
0.16: x
2x/2=0.64/2
x=0.32g/moles of nitrogen dioxide
then you use the formula for the volume
v=22.4n
=22.4×0.32
=7.2
I hope this helps
Which of the following is a common property of both strong acid and strong base?
a. They are good electrolytes
b. They are non-electrolytes
c. They are weak electrolytes
d. They are sour in test
Answer:
They are good electrolytes
The atomic mass of calcium is calculated by adding the mass (amount) of
A) Protons and Electrons
B) Protons and Neutons
C) Electrons and Neutons
D) Protons and Protons
Answer:
B. Protons and Neutrons
Answer:
Option"B" is correct.
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Which sentence describes existing cells?
All cells, once formed, continue to live forever.
All cells come from previously existing cells.
All the cells that are on Earth have always been here.
All cells develop from the remains of other cells.
potassium permanganate + water = ? which product will they form,and in which phase is it?
KMnO4 + H2O = MnO2 + O2 + KOH
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The boiling point of water is 100ºC. The boiling point of acetone is 56ºC. Which statement about distilling a mixture of acetone and water is correct?
Acetone remains in the original container.
Water will vaporize from the mixture before acetone.
Acetone is captured and cooled.
Water is collected as it leaves the mixture.
Answer:
Acetone is captured and cooled.
Explanation:
The boiling point of acetone is lower than that of water, so it will vaporise before water. Then acetone will be captured and cooled to separate it from its mixture with water.
The statement which is correct about distilling a mixture of acetone and water is as follows:
Acetone is captured and cooled.Thus, the correct option is C.
What is Distillation?Distillation may be defined as a procedure that generally involves the conversion of a liquid into a vapor that is eventually condensed back to liquid form. With the help of this process, the separation of components or substances from a liquid mixture by using selective boiling and condensation occurs.
Acetone has the lowest boiling point as compared to water. So, it boils faster than that water and vaporizes before water. After the termination of this process, the acetone will be predominantly captured and cooled to separate it from its mixture with water.
Therefore, the correct option for this question is C.
To learn more about the Boiling point of acetone, refer to the link:
https://brainly.com/question/17467265
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Convert 48,987 minutes to years
using the method of dimensional analysis
Answer:
Explanation:
48000 minutes [ 1 hour / 60 min ] 1 day / 24 hours ] [365 days / year]
48000 * [ 1/(60 * 24 * 365)]
48000 * [1 / 525600]
There are 0.0930954years in 48000 minutes
True or false, The four units that must always be used when using the ideal gas are 44.0 liters
Answer:
for volume only liters can be used
Explanation:
what apparatus is used to investigate the conductivity of solutions
Noble gases are the least reactive elements on the periodic table.
A. True
B. False
Answer:
The statement is True!"Why?"The Noble Gases have eight valence electrons, which fill their outer energy level. This is the most stable arrangement of electrons, so noble gases rarely react with other elements and form compounds.
Hope this helps!
Please help with the Volume one
Answer:
im a just achild
Explanation:
Answer:
c
Explanation:
0.5dm³
follow me if you want
Which of the following molecules contains six bonding electrons?
A C2H4
B CO2
C H2S
D NCl3
Answer:
c2h4 (etthane........
bexcuse it has 6 bond of hydrogen
C₂H₄ molecules contains six bonding electrons. Therefore, option A is correct.
What do you mean by the term bonding ?Chemical bonding is the process through which two or more atoms, molecules, or ions establish a chemical link to create a chemical compound. The atoms in the resultant molecule are held together by these chemical bonds.
Chemical bonds have three basic characteristics that must be taken into account: their strength, length, and polarity. The distribution of electrical charge among the atoms connected by a bond determines its polarity.
C₂H₄ molecules has six bonding electrons. This molecule is called as Ethylene. When bonding is done between two atoms, each atom shares a pair of electrons with each other.
Hence, for every one bond, two electrons are shared between two atoms
Thus, option A is correct.
To learn more about the bonding, follow the link;
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what is a cubic unit cell ?
cubic unit cell is the smallest repeated unit which have all angles equal to 90 and all have edge lengths equal
It is the type of the Unit cell which is having all angles equal to 90 and all sides equal to each other
it's is a unit cell with cubic structure
Which equation describes a physical change? i. H2O(s) ⟶ H2O(l) ii. Na+(aq)+Cl−(aq) +Ag+(aq)+NO3−(aq) ⟶ AgCl(s)+Na+(aq)+NO3−(aq) iii. CH3OH(g)+O2(g) ⟶ CO2(g)+H2O(g) iv. 2H2O(l) ⟶ 2H2(g)+O2(g) v. H+(aq)+OH−(aq)⟶ H2O(l)
Answer:
The answer is "Option i"
Explanation:
In this question, only option (i) is correct, and others were wrong which can be defined as follows:
In option (ii):
[tex]Na^+\ (aq)+Cl^- \ (aq) +Ag^+ \ (aq)+NO_3^- \ (aq) \to AgCl\ (s)+Na^+ \ (aq)+NO_3^-\ (aq) \\\\[/tex]
It is the complete ionic equation.
In option (iii):
[tex]CH_3OH\ (g)+O_2\ (g) \to CO_2\ (g)+H_2O\ (g)[/tex]
It is the combustion reaction but a not balanced equation.
In option (iv):
[tex]2H_2O\ (l) \to 2H_2\ (g)+O_2\ (g)[/tex]
It is the decomposition equation.
In option (v):
[tex]H^+\ (aq) +OH^-\ (aq)\to H_2O\ (l)[/tex]
It is the complete ionic equation.
what is meant by reaction element
Answer: A reaction element are those elements that can take part in a chemical reaction.
Explanation:
An element is made up of atoms that has the same atomic number. It is the basic material of which all matter is composed of. These elements cannot be broken down further into smaller substances by any chemical reaction. Each element has a unique number of protons in its atom. For example,
--> a hydrogen atom has 1 proton,
--> a Helium atom has 2 protons,
--> a Lithium atom has 3 protons, and
--> a carbon atom has 6 protons.
A chemical reaction on the other hand involves rearrangement of the constituent atoms of reactants to create different substances as products. The bonds between atoms are either broken or created to form new molecules. There are different types of chemical reaction which includes:
--> Decomposition reaction
--> Neutralization reaction
--> single displacement reaction and
--> combustion reaction.
how can we separate the sugar from sugar solution
All three states of matter can be ____________ or a solvent in a solution.
What is known about a reaction with a positive enthalpy?
Answer:
"Endothermic reaction: In an endothermic reaction, the products are higher in energy than the reactants. Therefore, the change in enthalpy is positive, and heat is absorbed from the surroundings of the reaction."
Explanation:
When enthalpy is positive and delta H is greater than zero, this means that a system absorbed heat. This is called an endothermic reaction. When enthalpy is negative and delta H is less than zero, this means that a system released heat. This is called an exothermic reaction.
What does a high positive enthalpy mean?
The sign of q for an endothermic process is positive because the system is gaining heat. A chemical reaction or physical change is exothermic if heat is released by the system into the surroundings. Because the surroundings are gaining heat from the system, the temperature of the surroundings increases.
Learn more about the endothermic reaction here: brainly.com/question/6506846
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Which of the following is true of science? (2 points)
It can be disproven by philosophy and religion.
It does not change after new evidence is discovered.
It is based on the personal opinions of scientists.
It is based on testable and replicable evidence.
Answer:
It is based on testable and replicable evidence.
Is water the only liquid? If not, name 5 more
Answer:
Is water the only liquid? If not, name 5 more
Water, ethanol, household bleach, blood, paint, milk, gasoline, mineral oil, acetone and butyl alcohol are examples of liquids. Liquids' properties allow them to flow or be poured easily into containers, lava
water is not the only liquid.
Answer:
apple juice, milk, smoothie, blood, urine
Calculate the amount of mole(s) of CoF2 required to react with 12.8 moles of HCI.
CoCl2 + 2HF --> CoF2 + 2HCI
Explanation:
here's the answer to your question
write an importance of endothermic reactions
Answer:
the uses of exothermic reactions are:
1) lighting of stove
2) self heating cans
3) hand warmers
4) in some case exothermic process can be used to cook food such as rice (by adding calcium oxide to water heat is evolved and it helps to cook food )
Explanation:
hope this helps you pls mark me as brainilst
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Which of these is an example of an example factor which affects the earths climate?
A - Decrease in the suns energy.
B - Warm and cold ocean currents.
C - Increase in atmospheric dioxide.
D - Release of dust during volcanic eruption
Answer:
D- Release of dust during volcanic eruption
Explanation:
During major explosive eruptions huge amounts of volcanic gas, aerosol droplets, and ash are injected into the stratosphere. Injected ash falls rapidly from the stratosphere -- most of it is removed within several days to weeks -- and has little impact on climate change. But volcanic gases like sulfur dioxide can cause global cooling, while volcanic carbon dioxide, a greenhouse gas, has the potential to promote global warming.
answer:
a - decrease in the suns energy.
explanation:
although the other options do discuss climate, temperature, etc., the sun DIRECTLY influences the earth's climate and would most likely affect it on a larger scale. for example, warm and cold ocean currents would affect the temperature of the ocean and could touch bay cities or islands, but they would not dictate the overall climate of the earth :)
♡ hopefully my reply helped you come to an answer~ please keep in mind that my response is purely that... MY response! i still have lots to learn, so please correct/educate me if you have found otherwise ♡
7. What measures are applicable in the context of Nepal to push energy crisis further. Describe any three points clearly.
Answer:
which energy?........
Explanation:
..........................
........
....
help me please I will mark as brainliest for the first correct answer
Answer:
1. 3-methylpentane
2. 2-bromo-3-chloropentane
3. 2,2,4-trimethylpentane
Explanation:
1. CH3CH2CH(CH3)CH2CH3.
Methyl group is in the third carbon atom in the long chain. The organic compound has five(5) carbon atoms thus it is named as pentane.
Therefore the name of the compound is
3-methylpentane
2. CH3CH(Br)CH(Cl)CH2CH3
The compound has Chlorine and Bromine in the carbon chain. Chlorine is given as chloro-, Bromine is given as bromo, depending on the position in the carbon chain. Bromine is located in 2 carbon atom and chlorine is in third(3) carbon atom in the long chain. The long chain has five carbon atoms thus pentane.
Naming of the compound we begin with the on lowest in the alphabet. The name of the organic compound is therefore;
2-bromo-3-chloropentane
3. CH3CH(CH3)3CH(CH3)CH2CH3
In this long chained organic compound, methyl-group is found in 2,2 and 4th positions. Since this is still pentane, naming the organic compounds, we start with the one with the lowest carbon. Therefore this becomes;
2,2,4-trimethylpentane
I hope this helps you to know how to name the organic compounds.
Please help I have been stuck on this problem for a couple hours and can't figure it out
Answer:
11.92 Liters O₂(g) at STP
Explanation:
For most stoichiometry problems, if one will convert all given data into moles, solve by rxn ratios, then finish by converting to needed dimensions to complete problem.
2Pb(NO₃)₂ => 2PbO + 4NO₂ + O₂
Given 237.5 grams PbO formed in reaction = 237.5 g/223.2 g/mole = 1.064 mole PbO
From equation ratios, moles O₂ formed = 1/2(moles PbO) = 1/2(1.064 moles O₂) = 0.532 mole O₂
0.532 mole O₂ = 0.532 mole x 22.4 liters/mole at STP = 11.91756272 liters (calculator answer) ≅ 11.92 liters O₂ at STP (4 sig.figs. based on given 237.5g PbO)
If ya could change somethin bout ya previous science classes what would it be?
If I could change something in my previous science classes, it would have been the fact that I struggled in the question concerning exponents. It was simple one, but I don't know how I didn't understood that. For example, if there is a question with a calculation "xy²", then I would first multiply x and y, and then calculate the exponent. I did 3 of the questions wrong because of this, it was when I was in 7th grade. I wish I had not done this kind of silly mistake. I an in 10th grade and understand it well now, though.
Can you help me on this. I will support your correct answer
Describe the principle and process for the manufractured of sulphuric acid witha a well labeled diagram by contact process.
The steps involved in the manufacture of sulphuric acid by contact process:
(1) Sulphur (or iron pyrites) are burnt in air to form sulphur dioxide.
S+O2→SO24FeS2+11O2→2Fe2O3+8SO2
(2) Catalytic oxidation of sulphur dioxide to sulphur trioxide.
2SO2+O2V2O52SO3ΔrHo=−196.6kJ
The reaction is reversible and exothermic.
(3) Sulphur trioxide is dissolved in 98% sulphuric acid to form oleum (fuming sulphuric acid).
SO3+H2SO4→H2S2O7
(4) Oleum is diluted with water to form sulphuric acid of desired concentration.
H2S2O7+H2O→2H2SO4
and
Manufacture of H2SO4 by contact process involves three steps:
1. Burning of sulphur in air to generate SO2.
2. Conversion of SO2 to SO3 by oxidation with air in the presence of
