Answer:
There's no single cause of depression. It can occur for a variety of reasons and it has many different triggers. For some people, an upsetting or stressful life event, such as bereavement, divorce, illness, redundancy and job or money worries, can be the cause. Different causes can often combine to trigger depression. For example, you may feel low after being ill and then experience a traumatic event, such as a bereavement, which brings on depression.
Why is the spot of drink placed above the water line at the start of the process
Make sure the area is higher than the solvent because if it isn't, the solvent will just wash it into the solution.
What is chromatography?Chromatography is defined as a technique for separation in which the analyte is mixed with a liquid or gaseous mobile phase and pushed through a stationary phase. Chromatography is a crucial biophysical method that makes it possible to separate, distinguish, and purify mixture's constituent parts for qualitative and quantitative study.
The sample may be lifted with more force thanks to the solvent, which also causes the sample to dissolve. Because of this, the start line in chromatography should always be above the solvent. To avoid getting an angled solvent front, it is crucial to ensure that the solvent is level and not at an angle.
Thus, make sure the area is higher than the solvent because if it isn't, the solvent will just wash it into the solution.
To learn more about chromatography, refer to the link below:
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How many moles is 2.04x1023 molecules of NH3?
Answer:
We will Multiply the number of moles with Avagadro's number
So it will be (2.04×1023)×6.022×10^23
or 2.04×1023 NANA means Avagadro's number
What statement can you make about how the behavior of the water particles changes when heat is added or removed?
Someone drops a book on the floor and it makes a loud noise. At the time you turn and look at the person who dropped the book .
In the scenario above turning and looking at the person who dropped the book is an example of a :
Answer: curiosity?
Explanation:
calculate the percentage mass of calcium chloride, CaCi^2
Answer: m-%(Ca) = 40.08 / 110.98
Explanation: molar mass of CaCl2 is 40.08+ 2·35.45 = 110.98
Think you have one mole substance. It contains 40.08 g Ca
help with my science about the human body
Answer:
am sorry what exactly is your question?
which element is shown in the picture here?
when solid copper chloride is mixed with water, a transparent blue solution is created. what is the copper chloride called?
Answer:
cuprous chloride
Explanation:
Copper dichloride
Copper(II) chloride
Copper(II) chloride/IUPAC ID
Match the box basically lol
In Which State of matter are molecules moving the slowest
A. Solid
B. Liquid
C. Gas
Answer:
Solid
Explanation:
Molecules in solids only vibrate in place, while the other two have moving molecules
What is the percent composition of hydrogen in glucose
Answer:
67%Explanation:
Thus the % composition of glucose by mass is carbon 40.0 % oxygen 53.3 % hydrogen 6.7 % in this way, the % composition by mass of any compound can be calculated provided that is formed is known.Best answer gets brainliest
Answer:
C) Mercury based thermometer
Explanation:
Answer:
Mercury based thermometer
Explanation:
When you touch a lightbulb it is warm. Hairdryer produces heat to dry your hair. Stove heats up to warm food and liquids up.
How many moles is equal 82.4 grams of CO,?
Answer:
1 mole = 28.0101
Hence,
82.4 = around 2.8 mole
Have a great day <3
The heat of combustion of ethane is -337.0kcal at 25 degrees celsius. what is the heat of the reaction when 3g of ethane is burnt completely
Answer:
Q = -33.6kcal .
Explanation:
Hello there!
In this case, according to the equation for the calculation of the total heat of reaction when a fixed mass of a fuel like ethane is burnt, we can write:
[tex]Q=n*\Delta _cH[/tex]
Whereas n stands for the moles and the other term for the enthalpy of combustion. Thus, for the required total heat of reaction, we first compute the moles of ethane in 3 g as shown below:
[tex]n=3g*\frac{1mol}{30.08g}=0.1mol[/tex]
Next, we understand that -337.0kcal is the heat released by the combustion of 1 mole of ethane, therefore, to compute Q, we proceed as follows:
[tex]Q=0.1mol*-337.0\frac{kcal}{mol}\\\\Q=-33.6kcal[/tex]
Best regards!
The heat of a reaction may be found with the equation q=mc triangle T. A 951 g sample of carbon steel with a specific heat capacity of 0.49 J/(g*K) is heated to 673K and quenched in oil. The steel cools to 523K. Assuming there is no heat lost to the surroundings, calculate the heat absorbed by the oil. A) -69.9kj B) -31.5kj C) 69.9 kJ D) 71.2 kj
Answer:b
Explanation:
Answer:
C.
Explanation:
I took the quiz and made a 100
Aspirin synthesis involves the addition of an acetyl group to salicylic acid in a condensation reaction with an alcohol. The acetyl group could be added with a carboxylic acid but the preferred procedure is to use the acid anhydride. Why is preferable to use an acid anhydride for ester formation with an alcohol rather than a carboxylic acid
Answer:
See explanation
Explanation:
The synthesis of asprin involves the;
i) Hydrolysis of Methyl salicylate
ii) Reaction of salicylic acid with acid anhydride
The chemical name of asprin is acetylsalicylic acid.
It is preferable to use an acid anhydride for ester formation with an alcohol rather than a carboxylic acid because we will not produce water which can then cause the hydrolysis of the newly formed ester.
When optically active (S)-2-methylcyclopentanone is treated with an acid (H3O ), the compound loses its optical activity. Explain this observation and draw a mechanism that shows how racemization occurs. For the mechanism, draw the curved arrows as needed. Include lone pairs and charges in your answer. Do not draw out any hydrogen explicitly in your products. Do not use abbreviations such as Me or Ph.
Answer:
See explanation
Explanation:
When (S)-2-methylcyclopentanone is treated with an acid, the carbonyl oxygen atom is protonated.
This leads to the emergence of a positive charge on the cabonyl oxygen. Then the C=O bond is now transformed into H-C-OH where C is a carbocation which leads to a racemic mixture. Loss of a proton from the adjacent carbon atom completes the mechanism.
In this process, the optically active (S)-2-methylcyclopentanone is converted to a pair of diastereomers thereby loosing its optical activity.
__C+_SO2—_CS2 + __CO
Answer:
_c+_so2-_cs2+_co= Toxic
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Which statement describes a process or step in the rock cycle?
A. Sediment must be compacted and cemented before it can change to sedimentary rock
B. Igneous rock must be melted and cooled before it can change to sedimentary rock
C. Sedimentary rock must condense before it can change to metamorphic rock
D. Sedimentary rock must cool before it can change to metamorphic rock
Consider a free lysine amino acid in a solution buffered to pH = 9.00. What will be the overall charge on the residue?
Is it -2, -1, 0, 1, 2?
Answer:
Explanation:
+1
The overall charge on the residue ( lysine residue ) is ; ( C ) 0 charge
The a-aminium group of lysine amino acid will begin deprotonating by the presence of NaOH as the pH level of the solution increases.
Given that the pKa level of a-aminium group = 9. when the pH of the solution is buffered to 9.0 . half of the a-aminium ions that is present in the lysine amino acid will deprotonate leaving the overall charge on the lysine residue at neutral ( 0 charge ).
Hence we can conclude that the overall charge on the residue is a 0 charge.
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Is water an element or compound
Answer:
Compound
Explanation:
H2O is made up of multiple types of atoms, which makes it a compound. It isn't an element because they only consist of one type of atom.
An iron sulfide compound is analyzed, and found to contain 11.26 g iron and 9.70 g sulfur. Determine the molar ratio of sulfur to iron in this compound, and hence its chemical formula.
Answer:
Molar ratio = 1.5Chemical formula = Fe₂S₃Explanation:
First we convert the given masses of each element into moles, using their respective molar masses:
Fe ⇒ 11.26 g ÷ 55.845 g/mol = 0.202 mol FeS ⇒ 9.70 g ÷ 32.065 g/mol = 0.302 mol SNow we divide them in order to calculate the molar ratio of S to Fe:
0.302 / 0.202 = 1.5Meaning that for each 1 Fe mol, there's 1.5 S moles. We can write that as Fe₁S₁.₅
Finally we double those subscripts so that they become the lowest possible integers: Fe₂S₃.
write acid formula where the non-metal element is has a valency of 6
Answer:
Hello ur answer is
Pyrosulphuric acid formula
Explanation:
thanks
Answer:
Hello There!!
Explanation:
The answer is=>Pyrosulphuric acid formula.
hope this helps,have a great day!!
~Pinky~
How many moles of LiOH are in a 4.5 M solution containing 1.5 L of water?
Answer:
d
Explanation:
Solid iron is mixed with a solution of copper (I) nitrate to form iron (III) nitrate solution and metal copper. what is the balanced equation?
If 6.70 g of zinc is reacted with 27.5 g of silver nitrate, the products will be zinc nitrate and silver metal. What is the theoretical mass of silver that will be produced?
a. Write a balanced equation
b. Interpret the equation by
particles and by moles
c. What is the limiting reactant?
Given:
Molar mass AgNO3 =
Needed:
unknown:
available:
d. What is the theoretical mass of silver that will be produced?
e. If the actual yield of silver was 14.1 g, what is the percent yield of the
reaction?
Explanation:
a. Write a balanced equation
The balanced equation for the reaction is given as;
Zn + AgNO3 → Ag + ZnNO3
b. Interpret the equation by particles and by moles
In this equation, 1mol of Zn reacts with 1 mol of AgNO3 to from 1 mol of Ag and 1 mol of ZnNO3
1 mol = 6.022 * 10^23 particles
c. What is the limiting reactant?
The mol ratio between both reactants is 1 : 1 from the equation.
Converting the masses given to ml;
Number of mol = Mass / Molar mass
Zn;
Number of mol = 6.70 / 65.38 = 0.1025 mol
AgNO3;
Number of mol = 27.5 / 169.87 = 0.1619 mol
The limiting reactant in this reaction is Zn. This is because Zn would get used up before AgNO3 according to the number of moles calculated.
d. What is the theoretical mass of silver that will be produced?
1 mol of Zn produces 1 mol of Ag
0.1025 mol of Zn would also produce 0.1025 mol mol of Ag
Mass = Molar mass * Number of Moles = 107.87 * 0.1025
Mass = 11.05 g
e. If the actual yield of silver was 14.1 g, what is the percent yield of the
reaction?
Percent yield = Actual Yield / Theoretical yield * 100%
Percent yield = 11.05 / 14.1 * 100 = 78.36%
How many moles of NaHCO3 are in 2.4 x
1024 molecules of NaHCO:?
4.0 moles NaHCO
General Formulas and Concepts:Math
Pre-Algebra
Order of Operations: BPEMDAS
Brackets Parenthesis Exponents Multiplication Division Addition Subtraction Left to RightChemistry
Atomic Structure
MolesAvogadro's Number - 6.022 × 10²³ atoms, molecules, formula units, etc.Stoichiometry
Using Dimensional AnalysisExplanation:Step 1: Define
[Given] 2.4 × 10²⁴ molecules NaHCO
[Solve] moles NaHCO
Step 2: Identify Conversion
Avogadro's Number
Step 3: Convert
[DA] Set up: [tex]\displaystyle 2.4 \cdot 10^{24} \ molecules \ NaHCO(\frac{1 \ mol \ NaHCO}{6.022 \cdot 10^{23} \ molecules \ NaHCO})[/tex][DA] Divide [Cancel out units]: [tex]\displaystyle 3.98539 \ moles \ NaHCO[/tex]Step 4: Check
Follow sig fig rules and round. We are given 2 sig figs.
3.98539 moles NaHCO ≈ 4.0 moles NaHCO
Lets make this one quick.
Calculate the [H+] for
(a) black coffee with a pH of 3.59