Answer:
Explanation:
E = (hc)/(λ)
E = (6.624x10^(-27))Js x ((3×10^8)ms^(-1)) /
(77.8x10^(-9)m)
E = 2.55 x 10^(-11) J
Pls help ASAP ! Identify the following reaction: H2 + O2 → H2O
Group of answer choices
synthesis reaction
decomposition reaction
single replacement reaction
double replacement reaction
Answer:
Synthesis Reaction
Explanation:
Here we see H2 and O2 are being combined H2O. Synthesis reactions are where we see a combination to make a single product.
So here it'd be A + B =AB
2Na(s)+Cl2(g)→2NaCl(s)
Decomposition would be the break down of a compound into 2, the opposite of synthesis.
AB = A + B
2HgO(s)→2Hg(l)+O2(g)
Single replacement is where 1 element replaces another in a reaction, or switches place with 1 element.
AY + B = A + BY
2 HCl(aq) + Zn(s) → ZnCl2(aq) + H2(g)
Double replacement is similar but 2 elements are switch/replaced.
AY + BX = AX + BY
CuCl2(aq) + 2 AgNO3(aq) → Cu(NO3)2(aq) + 2 AgCl(s)
If carbon is in an animal is it:
A. Abiotic matter
B. Biotic matter
C. Energy storage molecules
D. Carbon dioxide
I WILL MARK BRAINLIEST IF YOU HELP!
Do not guess or give me a file or I will report you!!
Answer:
It is A
Explanation:
Abiotic matter
Section I: Experimental Overview
Provide background information.
Include the hypothesis(es).
Summarize the procedures.
Section II: Data and Observations
Summarize the data you collected in the lab guide.
Include information from data tables.
Include any written observations that are relevant.
Section III: Analysis and Discussion
Discuss any important calculations or formulas used.
Identify key results, what the results indicate, and any trends in the data.
Include graphs (if constructed) that display trends in the data.
Provide possible reasons for any problems with the experiment, or unexpected data.
Section IV: Conclusions
Identify if the hypothesis(es) was (were) supported or refuted.
Provide logical reasoning based on data.
Explain how the experiment could be improved.
To help you write your lab report, you will first answer the questions listed below by reflecting on the experiment you have just completed. Then you will use the answers to these questions to write the lab report that you will turn into your teacher.
You can upload your completed report with the upload tool in formats such as , Microsoft Word, or PDF. Alternatively, your teacher may ask you to turn in a paper copy of your report or use a web-based writing tool.
Questions
Section I: Experimental Overview
What is the purpose of the lab, the importance of the topic, and the question you are trying to answer?
What is your hypothesis (or hypotheses) for this experiment?
What methods are you using to test this (or each) hypothesis?
Section II: Data and Observations
Locate the data and observations collected in your lab guide. What are the key results? How would you best summarize the data to relate your findings?
Do you have quantitative data (numerical results or calculations)? Do you have qualitative data (written observations and descriptions)? How can you organize this date for your report?
Section III: Analysis and Discussion
What do the key results indicate?
If you constructed graphs, what trends do they indicate in your data?
Answer:
If you constructed graphs, what trends do they indicate in your data?
For each of the following, predict the complete, balanced chemical equation for the reaction that occurs when they are mixed. Make sure to label the states.
1. HNO3 & NaOH
2. Sr(OH)2 & HI
..
Answer:
1. The balanced chemical reaction is:
[tex]HNO_3(aq)+NaOH(aq)\rightarrow NaNO_3(aq)+H_2O(l)[/tex]
2. The balanced chemical reaction is:
[tex]2HI(aq)+Sr(OH)_2(aq)\rightarrow SrI_2(aq)+2H_2O(l)[/tex]
Explanation:
Hello there!
In this case, according to the given chemical reactions, it is necessary to keep in mind the cations and anions are switched around as a result of the bonds rearrangement in these neutralization reactions; therefore, we can proceed as follows:
1. The balanced chemical reaction is:
[tex]HNO_3(aq)+NaOH(aq)\rightarrow NaNO_3(aq)+H_2O(l)[/tex]
Because all atoms are in the same amount at each side of the equation and the resulting salt is soluble.
2. The balanced chemical reaction is:
[tex]2HI(aq)+Sr(OH)_2(aq)\rightarrow SrI_2(aq)+2H_2O(l)[/tex]
Because all atoms are in the same amount at each side of the equation and the resulting salt is soluble.
Best regards!
Compare the ionization energies of each pair of atoms. Enter the symbol for the atom with the larger ionization energy.
(If both atoms would be expected to have the same ionization energy, enter the word same.)
Pairs Symbol of atom with the larger ionization energy
Cl and I
Na and K
F and Br
Answer: 1. I
2. Na
3. F
Explanation:
Ionization energy is the energy required to remove the most loosely bound electron from an isolated gaseous atom.
In a group, the ionization energy decreases as we move down a group as the size increases. The electrons get added to the next shell. Thus the valence electron moves far from the nucleus and thus less energy is required to remove the valence electron.
1. Cl and I: Cl will have larger ionization energy as I lies lower in the group.
2. Na and K : Na will have larger ionization energy as K lies lower in the group
3. F and Br : F will have larger ionization energy as Br lies lower in the group.
what changes would you see in the colour of litmus paper in lemon,ash and blood
Answer:
Colour of litmus papers in lemon:
Blue litmus- Red
Red litmus- No change
Really sorry but don't know about others
Litmus paper indicator shows following color changes for lemon it is, blue litmus to red, for ash and blood it is red litmus to blue indicating their acidic nature in case of lemon and alkaline nature in case of ash and blood.
What is an indicator?Indicator is defined as a chemical substance which is chemically a weak acid or a weak base which changes it's color depending upon the concentration of hydrogen ions present in the solution.They dissociate slightly in water to produce ions.
These are generally derived from plant pigments and are of slightly acidic or basic in nature.There are three types of indicators:
1) natural indicators
2) synthetic indicators
3) olfactory indicators.
These are mainly used in determination of end point of titrations. Every indicator has it's pH range in which it can perform effectively.These are usually organic compounds.
Learn more about indicators,here:
https://brainly.com/question/12489874
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Organelles that use energy from sunlight to produce food are called mitochondria
O True
O False
Answer:
Organelles that use energy from sunlight to produce food are called mitochondria.
False
Part A. Classify each of these soluble solutes as a strong electrolyte, a weak electrolyte, or a nonelectrolyte. Solutes Formula Nitric acid HNO3 Potassium hydroxide KOH Formic acid HCOOH Ethyl amine CH3CH2NH2 Sodium bromide NaBr Butanol C4H9OH Sucrose C12H22O11
Part B. Enter a molecular equation for the reaction that occurs between aqueous HBr and aqueous LiOH.
Answer:
1. Strong electrolytes = Nitric acid HNO3,Potassium hydroxide KOH, Sodium bromide NaBr
Weak electrolytes = Formic acid HCOOH Ethyl amine CH3CH2NH2, Butanol C4H9OH
Non-electrolyte = Sucrose C12H22O11
2. The reaction between aqueous HBr and aqueous LiOH is shown innthe equation below:
HBr + LiOH ----> NaBr + H₂O
Explanation:
Electrolytes are substances that when in molten state or in aqueous solution dissociate into ions both positively-charged and negatively-charged ions known as actions and anions, which are then able conduct electricity.
Strong electrolytes are aqueous or molten solutions of compounds which ionize completely to produce anions and actions. Ionic compounds such as organic salts, acids and bases are strong electrolytes.
Weak electrolytes only ionize partially, that is, they produce few ions. Some organic salts, acids and bases are weak elctrolytes
From the compounds given above;
Strong electrolytes = Nitric acid HNO3,Potassium hydroxide KOH, Sodium bromide NaBr
Weak electrolytes = Formic acid HCOOH Ethyl amine CH3CH2NH2, Butanol C4H9OH
Non-electrolyte = Sucrose C12H22O11
2. The reaction between aqueous HBr and aqueous LiOH is shown innthe equation below:
HBr + LiOH ----> NaBr + H₂O
A sample of N 2 gas has a volume of 30.0 ml at 25 degrees * C and 730 mmHg. What would be the volume of the gas at 50 ^ 0 * C and 1 atm pressure? a. 31.2 ml b. 26.6 mL c. 33.9 ml d. 57.6 ml
Answer:
your answer is D. 57.6
Explanation:
730+30.0+25+2=
Can somebody please help me!!
Answer:
acceleration
pls dont report me
Q) Briefly describe how body systems work all together
Answer:
Your bones and muscles work together to support and move your body. Your respiratory system takes in oxygen from the air. ... Your circulatory system carries oxygen, water, and nutrients to cells throughout your body. Wastes from the cells are eliminated by your respiratory system, your excretory system, and your skin.
Explanation:
please answer's these scientist answer's
A scientist observes that the leg bones of cats are similar to the bones in the wings of bats. The scientist concludes the two species share a common ancestor. Which describes why the scientist drew that conclusion?
1. developmental patterns
2. DNA
3. fossil evidence
4 .structural data
Bald eagles might lay up to five eggs at a time, but only one hatchling usually survives. Which feature of natural selection is this an example of?
1 .adaptation
2. genetic variation
3. overproduction
4. selection
By which method the following mixture can be separated?(i)mixture of colours (ii) Minerals oil.
Answer:
mixture of colours answer
A study was created to test the effects of fear in children. The hypothesis of the experimenters was that if babies were exposed to fuzzy bunnies and at the same time a loud cymbal was struck close behind them, then that child would be afraid of all fuzzy things. Another group of children would be exposed to bunnies without any loud noises. The study was carried out as planned and as a result, hundreds of young children developed fear of all cute furry bunny rabbits.
Dependent Variable: ______________________
Control Group: ____________________________
Independent Variable: _____________________
Experimental Group: _______________________
Answer:
Dependent variable: the children's fear of rabbits
Control: the group that was NOT exposed to loud noises
Independent variable: the loud noises
Experimental Group: the group that was exposed to loud noises
An orgo lab student named Bob wanted to synthesize an isoamyl acetate ester because it smells like bananas and he really likes to sniff it. He heated 7.50 grams of isoamyl alcohol (3-methyl-1-butanol) with 22.5 grams of acetic acid (ethanoic acid) and 4.50 grams of sulfuric acidto prepare his favorite ester. Based on these numbers, how many grams of isoamyl acetateshould he theoretically obtain
Answer:
The answer is "11.07 g".
Explanation:
Isoamyl alcohol is a reagent restriction
Isoamyl alcohol Moles:
[tex]= \frac{7.5}{88.15} \\\\ =0.085[/tex]
Moles only with the shape of isoamyl acetate are equivalent to numbers.
Isoamyl acetate grams:
[tex]= 0.085 \times 130.19\\\\ = 11.07 \ g[/tex]
Can somebody please help me!!!!
Answer:
Friston to energy
Explanation:
Friction to Energy as its a energy stooping the object form moving
Please help it’s for 100 points
Has your cell phone ever not had enough battery when you really needed it? What did you do?
Answer:
Yes
Explanation:
There are some times when I will need my cell phones but it will have not battery. At this point, I look for a means to charge it or I could probably use power bank to charge. I always have an extra battery, so when the other battery is flat, I will replace it with the second charged one. But when both batteries are flat, I will look for a means to charge it using generator or wait till I have access to power supply.
Does all of the liquid water in the atmosphere fall as rain? Why or why not?
3.
Balance the following reactions.
i)
Mg +
HCI →
MgCl2 +
H2
ii)
Mg(OH)2 +_
HCI →
MgCl2 +
H20
AgNO3 +
K3PO4 →
Ag3PO4 +
KNO3
iv)
H2SO4 +
Pb(OH)4 →
Pb(SO4)2 +
H2O
v)
Ca (OH)2 +
H3PO4 →
Ca3(PO4)2 +
H20
Answer: i) [tex]Mg+2HCl\rightarrow MgCl_2+H_2[/tex]
ii) [tex]Mg(OH)_2+2HCl\rightarrow MgCl_2+2H_2O[/tex]
iii) [tex]3AgNO_3+K_3PO_4\rightarrow Ag_3PO_4+3KNO_3[/tex]
iv) [tex]2H_2SO_4+Pb(OH)_4\rightarrow Pb(SO_4)_2+4H_2O[/tex]
v) [tex]3Ca(OH)_2+2H_3PO_4\rightarrow Ca_3(PO_4)_2+6H_2O[/tex]
Explanation:
According to the law of conservation of mass, mass can neither be created nor be destroyed. Thus the mass of products has to be equal to the mass of reactants. The number of atoms of each element has to be same on reactant and product side. Thus chemical equations are balanced.
The balanced chemical reactions will be:
i) [tex]Mg+2HCl\rightarrow MgCl_2+H_2[/tex]
ii) [tex]Mg(OH)_2+2HCl\rightarrow MgCl_2+2H_2O[/tex]
iii) [tex]3AgNO_3+K_3PO_4\rightarrow Ag_3PO_4+3KNO_3[/tex]
iv) [tex]2H_2SO_4+Pb(OH)_4\rightarrow Pb(SO_4)_2+4H_2O[/tex]
v) [tex]3Ca(OH)_2+2H_3PO_4\rightarrow Ca_3(PO_4)_2+6H_2O[/tex]
If 175.6 joules of energy are applied to a sample of Aluminum and its temperature changed by 35.4 degrees then what was the weight of the Aluminum sample?
Answer:
5.51g
Explanation:
Using the following formula:
Q = m × c × ∆T
Where;
Q = amount of heat in Joules
m = mass/weight of Aluminum
c = specific heat of Aluminum (0.900 J/g°C)
∆T = change in temperature.
Based on the information given in this question, Q = 175.6 joules, ∆T = 35.4°C, c = 0.900 J/g°C.
Using, Q = m × c × ∆T
175.6 = m × 0.900 × 35.4
175.6 = 31.86m
m = 175.6/31.86
m = 5.51g
The weight of the aluminum sample is 5.51g.
Why is NH3 not considered a base under the Arrhenius definition of acids and bases?
SELECT AN ANSWER
a. It does not react with acids.
b. NH3(aq) does not contain OH- ions.
c. NH3 is considered a base under the Arrhenius definition, but not under the Bronsted-Lowry definition.
d. It does not cause a color change when mixed with an acid-base (pH) indicator.
Answer:
b. NH3(aq) does not contain OH- ions.
Explanation:
According to Arrhenius in his definition, a base is a substance that has the ability to increase the hydroxyll ion (OH-) of an aqueous solution. In other words, Arrhenius bases dissociates into OH- when dissolved in water.
According to this question, ammonia (NH3) will not be considered an Arrhenius base because it does not contain OH-. This means that ammonia (NH3) cannot dissociate into hydroxyll ion when dissolved in water.
A mixture of gaseous reactants is put into a cylinder, where a chemical reaction turns them into gaseous products. The cylinder has a piston that moves in or out, as necessary, to keep a constant pressure on the mixture of . The cylinder is also submerged in a large insulated water bath. (See sketch at right.) From previous experiments, this chemical reaction is known to release of energy. The position of the piston is monitored, and it is determined from this data that the system does of work on the piston during the reaction.
Answer:
It is exothermic in nature.
Explanation:
(1) The reaction is exothermic in nature because it releases heat energy.
(2) Yes, the temperature of the water go up as the reaction releases heat energy and the temperature cool down as the heat energy is completely removed from the water.
(3) The piston move in when the pressure in the cylinder decreases and the piston move out when increase of pressure occur.
(4) As the outside movement of piston occurs, so we can say that the gas mixture does work on its surroundings.
(5) The system released 244 kJ of energy, in which only 150 kJ went into the water, then the difference must be the work done by the system on its surroundings.
W = (244 - 150) kJ = 94 kJ
"The sun was setting behind the mountain when Isaiah reached the first fields of crops, bordered by low white stone walls. At the end of the road was the village, built on a slope, whose houses sank with all their weight into the ground, as if in fear of sliding further down. Roofs of overlapping slates peered down on the tiny, lifeless windows. The tall wooden chimneys, shaped like truncated pyramids, smoked quietly in the evening. This place was the extreme point where men had dared to plant a shelter and sow the grain. But, on the rough, rocky soil, even the rye did not grow well. The old men died without having saved anything, and the young, one after the other, fled from this corner of bad earth that the snowfalls isolated from the world for six months of the year. Once prosperous and populated to the rim, the village now had barely eighteen fires. And above it there were only shelters lost in the mountains for summer climbers. "
1.This description allows us to identify the village of the two brothers as being mainly
a. An isolated high mountain village in which the inhabitants work hard and see their efforts rewarded.
b. A quiet high-altitude village in which many courageous young farmers live.
c. A village in total harmony with the wilderness that still can't feed its children.
d. A pleasant village in the heart of the rugged mountains that welcomes many climbers in summer.
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This is bob. If you brainliest him. He will reward you with a certain script.
what is your experience about water pollution
Answer:
water pollution is a process in which water gets polluted due to discharge of city sewage and industrial waste. I was suffering through the water born disease when I drank the contaminated water. The sources of water becomes dirty. It makes environment unbalanced. People suffer from different water born disease when they drink polluted water.
what is the xonclusion of separating acetone and water by simple and fractional distillation
Answer:
In conclusion, acetone was determined to be the unknown used in the simple distillation and acetone- water was separated successfully by fractional distillation. Introduction Distillation is the chief technique used to separate and purify liquids.
What is the pressure, in mmHg, of a 4.00 g sample of O2 gas, which has a temperature of 37.0 °C, and a volume of 4400 mL?
Answer:
549.48 mmHg
Explanation:
We'll begin by calculating the number of mole of oxygen in 4 g. This can be obtained as follow:
Molar mass of O₂ = 2 × 16 = 32 g/mol
Mass of O₂ = 4 g
Mole of O₂ =?
Mole = mass /molar mass
Mole of O₂ = 4/32
Mole of O₂ = 0.125 mole
Next, we shall convert 37.0 °C to Kelvin temperature. This can be obtained as follow:
T(K) = T(°C) + 273
T (°C) = 37.0 °C
T(K) = 37.0 °C + 273
T(K) = 310 K
Next, we shall convert 4400 mL to L.
1000 mL = 1 L
Therefore,
4400 mL = 4400 mL × 1 L / 1000 mL
4400 mL = 4.4 L
Next, we shall determine the pressure. This can be obtained as follow:
Number of mole (n) = 0.125 mole
Temperature (T) = 310 K
Volume (V) = 4.4 L
Gas constant (R) = 0.0821 atm.L/Kmol
Pressure (P) =?
PV = nRT
P × 4.4 = 0.125 × 0.0821 × 310
Divide both side by 4.4
P = (0.125 × 0.0821 × 310) / 4.4
P = 0.723 atm
Finally, we shall convert 0.723 atm to mmHg.
1 atm = 760 mmHg
Therefore,
0.723 atm = 0.723 atm × 760 mmHg / 1 atm
0.723 atm = 549.48 mmHg
Thus, the pressure is 549.48 mmHg
1. How many grams are in 1.4 moles of Mg(NO3)2?
Explanation:
molar mass of the compound = 24 + 2× 14+ 16×6
= 24 + 28 + 96
= 148g/mol
no of moles = given mass / molar mass of the compound
1.4 = given mass/ 148
1.4×148=given mass
207.2 g
Convert 467.00 g AlCl3 to mol AlCl3.
Answer:
467.000g AICI3 to mol AICI3
Explanation
Answer:
7.49959 mol i hope this is right
need help i only have 5 more minutes left
Answer:
Bleach, seawater, blood, water, coffee, orange, lemon
Explanation:
The pH is a measurement in chemistry defined as the -log [H⁺]. pH is used in quality control of materials. The pH is a scale from 1 (Acids) to 14 (Bases). The pH of 7 is for neutral solutions
Based on the information of the image, the most basic is bleach, then the seawater, the blood, water (Neutral), coffee, orange and, the most acidic is lemon.
The order is:
Bleach, seawater, blood, water, coffee, orange, lemonA 17.11 gram sample of an organic compound containing only C, H, and O is analyzed by combustion analysis and 21.71 g CO2 and 5.926 g H2O are produced. In a separate experiment, the molar mass is found to be 104.1 g/mol. Determine the empirical formula and the molecular formula of the organic compound. Enter the elements in the order C, H, O empirical formula
Answer: The empirical formula and the molecular formula of the organic compound is [tex]CHO[/tex] and [tex]C_4H_4O_4[/tex] respectively.
Explanation:
The chemical equation for the combustion of hydrocarbon having carbon, hydrogen and oxygen follows:
[tex]C_xH_yO_z+O_2\rightarrow CO_2+H_2O[/tex]
where, 'x', 'y' and 'z' are the subscripts of Carbon, hydrogen and oxygen respectively.
We are given:
Mass of [tex]CO_2[/tex] = 21.71 g
Mass of [tex]H_2O[/tex]= 5.926 g
Molar mass of carbon dioxide = 44 g/mol
Molar mass of water = 18 g/mol
For calculating the mass of carbon:
In 44g of carbon dioxide, 12 g of carbon is contained.
So, in 21.71 g of carbon dioxide, =[tex]\frac{12}{44}\times 21.71=5.921g[/tex] of carbon will be contained.
For calculating the mass of hydrogen:
In 18g of water, 2 g of hydrogen is contained.
So, in 5.926 g of water, =[tex]\frac{2}{18}\times 5.926=0.658g[/tex] of hydrogen will be contained.
Mass of oxygen in the compound = (17.11) - (5.921+0.658) = 10.53 g
Mass of C = 5.921 g
Mass of H = 0.658 g
Mass of O = 10.53 g
Step 1 : convert given masses into moles.
Moles of C =[tex] \frac{\text{ given mass of C}}{\text{ molar mass of C}}= \frac{5.921g}{12g/mole}=0.493moles[/tex]
Moles of H=[tex]\frac{\text{ given mass of H}}{\text{ molar mass of H}}= \frac{0.658g}{1g/mole}=0.658moles[/tex]
Mass of O=[tex]\frac{\text{ given mass of O}}{\text{ molar mass of O}}= \frac{10.53g}{16g/mole}=0.658moles[/tex]
Step 2 : For the mole ratio, divide each value of moles by the smallest number of moles calculated.
For C =[tex]\frac{0.493}{0.493}=1[/tex]
For H =[tex]\frac{0.658}{0.493}=1[/tex]
For O=[tex]\frac{0.658}{0.493}=1[/tex]
The ratio of C : H: O = 1: 1: 1
Hence the empirical formula is [tex]CHO[/tex].
empirical mass of CHO = 12(1) + 1(1) + 1 (16) = 29
Molecular mass = 104.1 g/mol
[tex]n=\frac{\text {Molecular mass}}{\text {Equivalent mass}}=\frac{104.1}{29}=4[/tex]
Thus molecular formula = [tex]n\times {\text {Empirical formula}}=4\times CHO=C_4H_4O_4[/tex]