Answer:
Explanyour mmation:
A sample of water has a mass of 193 g. Salt is added to the water, and the final solution weighs 238 g. How much salt was added? Please help no rush needed but this is due today but no rush..........Thank you so much.
Answer:
45 g of salt was added
Explanation:
238g-193g=45g
Liquid boils faster at mountain region than in terai region. why?
Answer:
are you silly your question is opposite silly
Answer:
beacuse this reason has lower atmospheric pressure due to a thinner blanket of air above. ... As atmospheric pressure decreases, liquid boils at lower temperatures. due to which it takes less time than terai region
The graph models the amount remaining, in milligrams, of a radioactive substance as a function of time, in years. Explain the meaning of the point (3100) shown on the graph. Answer in complete sentences.
Answer:
Where is the grahppppp?!!!!
I’m trying to answer this question
Answer:
her speed is constant as she runs, and her av. speed is 3 m/sec
Explanation:
av speed is total distance divided by total time, so 150/50=3
Calculate the mass in grams of each of the followinga. 5.94 x 10^20 H2O2 moleculesb. 2.8 x 10^22 SO2 moleculesc. 4.5 x 10^25 O3 moleculesd. 9.85 x 10^19 CH4 molecules
Answer:
[tex]0.0335\ \text{g}[/tex]
[tex]2.978\ \text{g}[/tex]
[tex]3586.84\ \text{g}[/tex]
[tex]0.0026\ \text{g}[/tex]
Explanation:
Mass in grams is given by
[tex]m=\dfrac{nM}{N_A}[/tex]
where
n = Number of molecules
[tex]N_A[/tex] = Avogadro's number = [tex]6.022\times 10^{23}\ \text{mol}^{-1}[/tex]
M = Molar mass of molecule
Molar mass of [tex]H_2O_2[/tex] = 34.0147 g/mol
[tex]n=5.94\times 10^{20}[/tex]
[tex]m=\dfrac{5.94\times 10^{20}\times 34.0147}{6.022\times 10^{23}}\\\Rightarrow m=0.0335\ \text{g}[/tex]
Mass of [tex]H_2O_2=0.0335\ \text{g}[/tex]
Molar mass of [tex]SO_2[/tex] = 64.066 g/mol
[tex]n=2.8\times 10^{22}[/tex]
[tex]m=\dfrac{2.8\times 10^{22}\times 64.066}{6.022\times 10^{23}}\\\Rightarrow m=2.978\ \text{g}[/tex]
Mass of [tex]SO_2=2.978\ \text{g}[/tex]
Molar mass of [tex]O_3[/tex] = 48 g/mol
[tex]n=4.5\times 10^{25}[/tex]
[tex]m=\dfrac{4.5\times 10^{25}\times 48}{6.022\times 10^{23}}\\\Rightarrow m=3586.84\ \text{g}[/tex]
Mass of [tex]O_3=3586.84\ \text{g}[/tex]
Molar mass of [tex]CH_4[/tex] = 16.04 g/mol
[tex]n= 9.85\times 10^{19}[/tex]
[tex]m=\dfrac{9.85\times 10^{19}\times 16.04}{6.022\times 10^{23}}\\\Rightarrow m=0.0026\ \text{g}[/tex]
Mass of [tex]CH_4=0.0026\ \text{g}[/tex]
Assume that a film includes repeated scenes showing the trademark Voom on the sports shoes of its attractive adolescent protagonists. Althoughthe film is successful among young audiences, no increase occurs in the sale of Voom shoes. Which of the following hypotheses about this outcome is the most plausible on the basis of the studies cited?
A) Audiences feel uncomfortable because Voom is an unfamiliar brand.
B) Most members of the audience already own a pair of Voom shoes.
C) Audiences are worried by the social implications of these scenes.
D) Audiences are too engrossed in the story to notice the shoes.
Answer: D
Explanation: Even if the audiance did not have a pair of shoes felt uncomfortable or worried not a lot of people would have noticed. If anyone noticed it would only be about 5% of people so that is how I came to the conclision of D.
What is the percent composition of carbon in K2CO3?
Answer:
8,68%
Explanation:
12g/mol de C divided by 138,2 g/mol de K2CO3
0.0868 x 100 = 8.68 %
What makes a compound
polar?
Answer:
Polar molecules occur when two atoms do not share electrons equally in a covalent bond. ... If the electronegativity difference between the atoms is greater than 2.0, the bond is ionic. Ionic compounds are extremely polar molecules.
Explanation:
The accepted value is 29.35. Which correctly describes this student's experimental data?
Answer:
- Both accurate and precise.
Explanation:
The experimental data is characterized as the data that is generated through a specific test or measurement with the purpose of analysis or evaluation. As per the question, the minuteness of the given data(29.27, 29.32, and 29. 27)most aptly describes that the experimental data collected by the student possesses 'accuracy and precision' apt and specific. It would yield the most worthy and reliable conclusion.
How many Joules of heat will be given off by 55.0g of water as it cools from 87.3°C to 25.0°C?
Answer:
Q = -14322.77 J
Explanation:
Given data:
Mass of water = 55.0 g
Initial temperature = 87.3°C
Final temperature = 25.0 °C
Heat given off = ?
Solution:
Specific heat capacity:
It is the amount of heat required to raise the temperature of one gram of substance by one degree.
Specific heat capacity of water is 4.18 J/g.°C
Formula:
Q = m.c. ΔT
Q = amount of heat absorbed or released
m = mass of given substance
c = specific heat capacity of substance
ΔT = change in temperature
ΔT = 25.0 °C - 87.3°C
ΔT = - 62.3 °C
Q = 55.0 g×4.18 J/g.°C × - 62.3 °C
Q = -14322.77 J
Which of the following most readily undergoes an E2 reaction with sodium ethoxide (NaOCH2CH3)?A) (CH3)CF.
B) (CH3)CCl.
C) (CH3)CBr.
D) (CH3)CI.
Answer:
(CH3)CI
Explanation:
As we move down the group, the halogen atoms become more easily polarizable and the C-X bond is more easily broken.
Recall that E2 mechanism has to do with synchronous proton abstraction and loss of the halogen.
These occur faster with (CH3)CI than when the C-X bond involves other halogens.
Explain the law of conservation of energy. Give a specific example using kinetic and potential energy that shows how energy is conserved.
Answer:
Law of conservation of energy states that energy can neither be created nor can be destroyed but can be changed from one form to another
example:I am quite confused Sorry....❤plz follow me
A rotameter calibration curve (flow rate versus float position) obtained using a liquid is mistakenly used to measure a gas flow rate. Would you expect the gas rate determined in this manner to be too high or too low?
Answer:
I would expect the gas rate determined in this manner to be too low
Explanation:
A Rotameter can be designed to respond to the sensitivity of density, velocity, to measure the flow rate of liquid or gas enclosed in a tube. Liquids are denser than gas, and since the gas rate to be determined needed to respond to the velocity head alone of the rotameter so as to bring the forces in the tube equilibrium. Knowing if there is no flow, then the float would remain at the bottom, so gas has to flow at a higher rate compared to the liquid so the float would be in a similar position making it easier to measure the flowrate. This leaves the gas rate to be determined too low.
What is the tightly stretched membrane that forms the entrance to the middle ear called?
Answer:
I'm so happy to help you with this question!! The answer is tympanic.
Explanation:
The middle ear is separated from the outer ear by the eardrum, or tympanic membrane, a thin piece of tissue stretched tight across the ear canal. Sounds hit the eardrum, making it move.
I really hope this helps you!! :)
what is the formula for calculating heat energy when there is a change in temperature.
Answer:
Q = m.c. ΔT
Explanation:
When temperature is changed the heat evolved or absorbed are calculating by following formula.
Formula:
Q = m.c. ΔT
Q = amount of heat absorbed or released
m = mass of given substance
c = specific heat capacity of substance
ΔT = change in temperature
Specific heat capacity:
It is the amount of heat required to raise the temperature of one gram of substance by one degree.
When temperature is decreased heat is evolved and negative sign is added into Q value.
When temperature is increased heat is absorbed by system and positive sign is added with Q value.
PLEASE HURRY FAST MY TEACHER SAID SHE WILL BE GRADING THIS AND IF WE DON'T DO IT WE WILL FAIL AND I AM ONE OF THE PEOPLE WHO DID NOT DO IT YET. Question: it says look at the table of some properties of three substances. Here are the three substance: X, Y, or Z. Color: light brown, light brown, dark brown. Texture: smooth ,rough, spongy. Smell: strong odor, strong odor, odor. NOW IT SAY. You are given a substance listed in this table. What is the best way to identify the substance as X, Y, or Z PLEASE HELP ME PLEASE. AND HERE ARE THE ANSWERS THEY GAVE US: A. feel it, b. look at the color, c. smell it, d. Find mass
Answer:
C. Smell it
Explanation:
Yolo it and if im right then i deserve a 5 star :)
Answer:
honestly If I were that person I would go with feeling to figure out the texture because thats the most distinctive thing but I could be wrong. Good Luck.
Explanation:
what are the harmful effects of water pollution
Answer:
- Reduced biodiversity
- Health problems from drinking the water
- Diseases
There are various types of pollution like air pollution, water pollution , noise pollution etc. Therefore, in below given ways we can see harmful effects of water pollution.
What is pollution?The introduction of hazardous elements into the environment is pollution. Pollutants are the name for these dangerous substances. They can also be brought by by human activities, such as factory runoff or waste.
Following are a few harmful outcomes of water pollution: The health and existence of humans, animals, and plants are all negatively impacted by water pollution. Because it harms crops and soil fertility, polluted water is also bad for agriculture. Ocean life suffers as a result of ocean water pollution.
Therefore, in above ways we can see harmful effects of water pollution.
To know more about pollution, here:
https://brainly.com/question/15032151
#SPJ2
Explain how the ability of dilute sulphuric (vi) acid to conduct an electric current compares with that of concentrated sulphuric (vi) acid
Answer:
Explanation:
Hnsnsnsnsnqnananana
Use the following balanced equation to answer the following questions:
CH4 + 2 O2 → CO2 + 2 H2O
For every 10 g of CH4 reacted, how many grams of CO2 is produced?
NEED ASAP
Answer:
27.5 gram
Explanation:
16 gram CH⁴ gives 44 gram CO²
1 gram CH⁴ gives 44/16 gram CO²
10 gram CH⁴ gives (44/16)×10 gram CO²=27.5 gram Co²
In contact freezing _____ are used for _____ freezing of foods
immersion -- cryogenic liquids
refrigerants -- immersion
immersion -- refrigerants
cryogenic -- immersion
Answer:
In contact freezing refrigerants are used for immersion freezing foods.
Explanation:
An imaginary planet was just discovered that has a similar environment to our planet Earth. All the chemistry is similar except for the values of bond energies. Use the planet's given bond energies to calculate the enthalpy of reaction for the combustion of 1 mole of pentane.
Enter a number to O decimal places in kJ/mol
Bond Energy (kJ/mol)
H-H 585
C-H 257
H-O 478
C-C 370
C C 779
CC 992
0-0 490
C-0 251
C-0 740
Answer: [tex]\Delta H_{rxn}=-4652[/tex] kJ/mol
Explanation: In a reaction, a bond of a molecule can break or rearrange itself. When it happens, it absorb or release energy.
Bond Energy is the energy necessary to break or to make a particular bond, producing gaseous fragments at atmospheric temperature. This type of energy can be used to show how stable a compound is or how easy a bond can break.
Enthalpy of Reaction is the energy absorption or release at a constant temperature resulting from a chemical reaction.
To calculate the Enthalpy using bond energy, you have:
1) Write the balanced equation with all the all the reactants and products in gaseous form:
[tex]C_{5}H_{12}_{(g)}+8O_{2}_{(g)}[/tex] ⇒ [tex]5CO_{2}_{(g)}+6H_{2}O_{(g)}[/tex]
2) Count each bond of each molecule from both sides, including double or triple bonding, if they exists:
Reactants:
[tex]C_{5}H_{12}[/tex] : 12 C-H
4 C-C
O₂ : 1 O=O
Products:
CO₂ : 2 C=O
H₂O : 2 H-O
3) From the balanced reaction, we there are 8 moles of oxygen gas, 5 moles of carbon dioxide and 6 moles of water, which has to be included when adding each side.
[tex]\Sigma H_{reactants}=[/tex] 12.257 + 4.370 + 8.490 = 8484
[tex]\Sigma H_{products}=[/tex] 5.2.740 + 6.2.478 = 13136
4) Calculate Enthalpy of Reaction by:
[tex]\Delta H_{rxn}= \Sigma H_{reactants}-\Sigma H_{products}[/tex]
[tex]\Delta H_{rxn}=8484-13136[/tex]
[tex]\Delta H_{rxn}=-4652[/tex]
The enthalpy of reaction for the combustion of 1 mole of pentane on a just discovered imaginary planet is an exothermic process of magnitude [tex]\Delta H_{rxn}=[/tex] - 4652kJ/mol
Using the planet's given bond energies to calculate the enthalpy of reaction, the combustion of 1 mole of pentane is -4652 kJ.
The balanced chemical reaction for the combustion of pentane is well represented as:
[tex]\mathbf{C_5H_{12}+8O_2 \to 5CO_2+6H_2O}[/tex]
From the above reaction, the bonds broken are 12 Carbon-Hydrogen bonds, 4 Carbon-Carbon bonds, and 8 oxygen-oxygen bonds.
Similarly, the bonds formed are 10 Carbon-Oxygen bonds and 12 Oxygen-hydrogen bonds.
Hence, the energy absorbed when bonds are broken are:
= 12(C-H) + 4(C-C) + 8(O-O)
= 12(257 kJ) + 4(370 kJ) + 8(490 kJ)
= 3084 kJ + 1480 kJ+ 3920 kJ
= 8484 kJ
Also, the energy released as a result of the formation of bond is:
= 10 (C=O) + 12 (O-H)
= 10 (740 kJ) + 12 (478 kJ)
= 7400 kJ + 5736 kJ
= 13136 kJ
From above, we can notice that the energy released during the formation of bonds is greater than the energy absorbed while breaking bonds.
Thus, the enthalpy of the combustion reaction is the difference in energy.
i.e.
The enthalpy of the combustion reaction = 8484 kJ - 13136 kJ
= -4652 kJ
Therefore, we can conclude that the enthalpy of reaction from the combustion of 1 mole of pentane is -4652 kJ. The negative sign indicates that more energy is released compared to the amount of energy absorbed.
Learn more about the enthalpy of reaction here:
https://brainly.com/question/1657608?referrer=searchResults
what the formula of bisethylenediphosphinecobalt(lll)-meu-imido-meu-
hydroxobisbipyridinecobalt(lll) ion.
Please help with at least one of these questions! I have about 15-20 mins left :(
1. Name 2 examples of a physical change and tell why they are physical changes and not chemical changes.
2. Name 2 examples of a chemical change and tell why they are chemical changes and not physical changes.
3. Gold and pyrite (fool's gold) cannot easily be distinguished by color? What other physical property/properties can be used to tell the 2 metals apart from one another?
Answer:
1. Melting ice does not change the composition of the water or ice, as the ice is only changing its state from solid to liquid. Boiling water also does not change the composition of the water or gas, as the water is only changing its state from liquid to gas.
2. Burning paper turns the paper fibres to ashes. Making yoghurt from milk is making something new out from milk, where there is fermentation going on to turn the lactose into an acid, resulting in a chemical change and not a physical change.
Explanation:
A chemical change is when a new substance is formed from the old thing due to a chemical process such as burning where energy is given off or absorbed, while a physical change is basically changing the state of a substance but its composition does not change, unlike a chemical change.
PLEASE HELP !!!! How many grams of lithium sulfate
(Li2SO4) are required to dissolve in
459 g of water to make a 1.23 m
solution?
[?]g Li2SO4
Molar mass of Li2SO4: 109.94 g/mol
Answer:
I think you need to dissolve 62.116 (or 62.12g) of Li2SO4 .
The mass of lithium sulfate needed is 62g
What is Molality?Molality is also known as molal concentration. It is a measure of solute concentration in a solution. The solution is composed of two components; solute and solvent.
It is defined as the moles of the solute present in 1kg of the solvent. It is denoted by 'm'.
This term is useful in understanding the concentration of a solution because its formula is independent of temperature and pressure. Thus, the colligative properties are dependent on molality.
Given,
Molality of solution = 1.23m
Mass of solvent ( water) = 459g
Molality = number of moles of solute ÷ mass of solvent in kg
number of moles of solute = molality × mass of solvent in kg
= 1.23 × 0.459
= 0.564 moles
moles = mass / molar mass
mass= 0.564 × 109.94
= 62 g
Therefore, the mass of lithium sulfate needed is 62g
Learn more about Molality, here:
https://brainly.com/question/26921570
#SPJ7
What Celsius temperature, T2, is required to change the volume of the gas sample in Part A (T1 = 42 ∘C , V1= 1.10×103 L ) to a volume of 2.20×103 L ? Assume no change in pressure or the amount of gas in the balloon.
Answer:
The temperature that is required is 357 C.
Explanation:
Charles's Law consists of the relationship that exists between the volume and the temperature of a certain quantity of ideal gas, which is maintained at a constant pressure, by means of a constant of proportionality that is applied directly. For a given sum of gas at a constant pressure, as the temperature increases, the volume of the gas increases and as the temperature decreases, the volume of the gas decreases because the temperature is directly related to the energy of the movement of the gas molecules. .
In summary, Charles's law is a law that says that when the amount of gas and pressure are kept constant, the ratio between the volume and the temperature will always have the same value:
[tex]\frac{V}{T} =k[/tex]
Now it is possible to assume that you have a certain volume of gas V1 that is at a temperature T1 at the beginning of the experiment. If you vary the volume of gas to a new value V2, then the temperature will change to T2, and it will be true:
[tex]\frac{V1}{T1} =\frac{V2}{T2}[/tex]
In this case:
V1= 1.10*10³ LT1= 42 C= 315 K (being 0 C=273 K)V2= 2.20*10³ LT2= ?Replacing:
[tex]\frac{1.10*10^{3}L }{315 K} =\frac{2.20*10^{3}L }{T2}[/tex]
Solving:
[tex]T2=\frac{2.20*10^{3}L }{ \frac{1.10*10^{3}L }{315 K} }[/tex]
T2=630 K= 357 C
The temperature that is required is 357 C.
50 pts
With 11 electrons how many electron shells does sodium have?
3
4
2
1
Answer: 3
Explanation:
Steve wants to investigate the expansion and contraction of gases at different temperatures. He knows that at higher temperatures, gas particles move faster. His hypothesis is that at higher temperatures the faster particle motion causes gas to expand. He fills three balloons with the same amount of gas and heats the gas in each balloon to different temperatures. The test (independent) variable is the temperature of the gas. Which statement describes how the outcome (dependent) variable changes as a result of the changes made to the tested (independent) variable?
Answer: C. Gas particles move faster and farther apart at higher temperatures.
Explanation:
The options include:
A. the number of gas particles increases at higher temperatures
B. the number of gas particles decreases at higher temperatures
C. gas particles move faster and farther apart at higher temperatures
D. gas particles move more slowly and get closer together at higher temperatures
The statement that describes how the outcome (dependent) variable changes as a result of the changes made to the tested (independent) variable is that gas particles move faster and farther apart at higher temperatures.
It should be noted that the particles in the gases will collide more frequently with one another because of the shorter space that is between them.
The increase in the temperature will bring about a faster movement of the particles which in turn, brings about a rise in the diffusion rate and also the collision rate.
Explain the 2 main differences between ionic and covalent bonds and identify if the compound CaF2
will have an ionic or covalent bond and why.
Answer:
yes. because look at the equation it will have an ionic bond
Explanation:
2. How can where you live affect the amount of available water to use?
Answer:
Water is life, as the saying goes. We rely on water for our food, our health, our livelihoods, and for fun and leisure. But water can also take away life, and the absence of water can be even worse. Currently, 700 million people live in water-stressed areas. By 2025, this number is expected to grow 1.8 billion — about 25% of the world population.
As Number 6 on the UN’s Sustainable Development Goals, “Clean Water and Sanitation For All” is currently struggling. The UN suggests that, if we want to meet this goal by the deadline of 2030, we’ll need to double our current rate of progress to ensure that there’s universal access to safe and affordable drinking water, adequate sanitation and hygiene resources, improved water quality, and restored water-related ecosystems. Here are 5 ways that water affects our lives — and what we’re doing to help make them happen.
Explanation:
Many of the towns we live in were built near water sources. Oceans, rivers, streams and lakes make up some of our geographical boundaries. They also allow for water transportation and commerce and provide food and other resources.
The elements in Groups 1 and 2 get more reactive as you go down the group.
This means that _______________ is more reactive than lithium and ____________________ is more reactive than beryllium.
Answer:
Sodium and Magnesium
Explanation:
The elements in Groups 1 and 2 get more reactive as you go down the group.
This means that Sodium is more reactive than lithium and Magnesium is more reactive than beryllium.
On the periodic table, as you go down the group, the reactivity of an element increases. Especially with metals in group 1 and 2. Now Lithium is a metal of group 1, followed by Sodium, while Beryllium is a metal in group 2, followed by magnesium. That's how I picked the answers