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Related Questions
1 When 25 cm of 1.0 mol/dmº copper sulfate solution was mixed vith an excess of zinc
powder, the temperature of the solution rose by 50.6 °C. Calculate the energy change
for the reaction in kJ/mol.
CuSO4(aq) + Zn(s) + Cu(s) + ZnSO4(aq)
?
Answers
Answer:
See explanation
Explanation:
From the formula for heat;
q (enthalpy change) = (mass of solution) x (specific heat capacity) x (temperature change)
Since the density and heat capacity of the solution are the same as that of pure water.
Mass of copper sulphate solution = 50 g
Heat = 50 * 4.18 * 50.6°C
Heat = 10575.4 J
Number of moles = 1 * 25/1000 = 0.025 moles
10575.4 J/ 0.025 moles = 432016 J/mol/1000
= 423 KJ/mol
or
q = - 423 KJ/mol
Can i titrate a solution of unknown concentration with another solution of unknown concentration and still get a meaningful answer
Answers
Answer:
No, I don't think so at least
Explanation:
In chemistry, you do calculations to find the concentration of a solution with another solution of KNOWN concentration. Without concentrations of either solution, were would you get values from? Where would you start? :3
You can not titrate a solution of unknown concentration with another solution of unknown concentration and still get a meaningful answer.
Titration involves the standardization of unknown solution using a standard solution. By this definition, titration must involve a standard solution.
Since the two unknown solutions are not standardized, we can never get a meaningful answer because we can not be able to perform any calculation unless we have a standard solution.
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Why is it important to know characteristics that matter undergoes in chemistry? How can we analyze the relationships between chemical and physical changes and properties?
Extension Questions: What is the study of Chemistry? Who are some of the important people who have contributed to the field? How do regular Americans interact with Chemistry around them?
How can we understand the historical development of the Periodic Table and apply its predictive power?
Extension Questions: Describe different chemical principles and systems. How does the layout of the periodic table allow you predict other element's properties? Consider all types and groups of elements.
Why is it important to know and understand the historical development of atomic theory?
Extension Questions: How does the atom relate to the elements of the periodic table? What are your most common models and how do they relate to the current atomic model? What theories don’t hold true today if any?
How do atoms combine to form ionic, covalent, and metallic bonds?
How can we write and balance chemical equations using the law of conservation of mass?
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Answer:
Chemistry is important because everything you do is chemistry! Even your body is made of chemicals. Chemical reactions occur when you breathe, eat, or just sit there reading. All matter is made of chemicals, so the importance of chemistry is that it's the study of everything.
Molar Mass:
Find the molar masses of the following compounds. Also report the number of atoms in the compound:
1) NaBr
2) PbSO4
3) Ca(OH)2
4) Na3PO4
5) (NH4)2CO3
6) C6H12O6
7) Fe3(PO4)2
8) (NH4)2S
9) Zn(C2H3O2)2
10) AgF
Answers
Answer:
Atomic models are important because, they help us visualize the interior of atoms and molecules, and thereby predicting properties of matter.
Explanation:
We study the various atomic models in our course of study because, it is important for us to know, how did people come to the present concept of an atom. How did physics evolve from classical to quantum physics.
All these are important for us to know and thus, knowledge about various atomic models, their discoveries and drawbacks and finally improvements based on scientific evidence present at that time is important for us to understand the underlying theory very well.
Explanation:
A DAY IN THE LIFE OF METIS JOURNAL. I WROTE IT HOPE U LIKE IT XD
We, who live in the west, were Nomadic. So we always moved from place to place to hunt buffalo and other fur-bearing animals. And now again we have to shift everything we collected , like, all the essential needs we collected. It’s really hard to shift stuff, But when you move to a new place you get to see new beautiful places. They are just so satisfying to see! It’s like all my work(like the shifting work) is paid off. I love it! We always meet the Hudson’s bay company employees, and give them furs which we took from the bissons and other furry animals we hunted. And in exchange they give us their (Hudson’s Bay company) goods. Which is good! Because then we or I won't be able to enjoy that delicious pemmican!
The one reason that makes me proud of my parents is that because of them I am like a translator for both sides in the fur trade! Anyways coming back to the present. As I said before, we were moving today to another place, But on the way some people along with my father will ride the famous York boats carrying supplies to fur posts. I begged my father to take me with him! And as usual he gave me some silly reason for me to stay. And now since I don’t have anything to do I will-..Nevermind, My mom’s calling me. Okay after helping my mom keep the fur posts into the York boats me , my mom, and the others are just relaxing and enjoying nature just to take a break. Since, I am so obsessed with my Journal notebook today I’m just going to sit here and right what comes to my mind. I’m not like the others who always seem to be talking with someone. I like my own space!
I kind of miss my dad already, but he and his fellow members need to travel the waterways from the red river further west and north to hudson bay. These red river carts also travel the trek back and forth over land to St. Paul, Minnesota and to posts in saskatchewan. Speaking about the red river, the only large settlement in the region is the red colony. About 12000 people lived in this colony around Fort Garry. Some were the original Selkirk settlers or their descendents. They had come from Scotland with lord Selkirk when he established the colony in 1811. Many of these original settlers were poor farmers who had been displaced from their lands in scotland. They had endured many hardships in the early years of settlement, including foods, hunger, and sickness. I love studying about other colonies, cultures , history etc.
In the atmosphere, it is more common to find two oxygen molecules joined together than to find a single atom of oxygen. Why? What would that molecule look like? What would this molecule be called?
Answers
Answer:
See explanation
Explanation:
Oxygen has six electrons in its outermost shell. This means that its octet can be completed when it shares two electrons with another oxygen atom.
In a covalent bond, each bonding atom contributes one electron to the bond. This means that four electrons are shared between two oxygen atoms. Each atom contributes a total of two electrons which are shared. This molecule of oxygen satisfies the octet rule rather than a single atom of oxygen.
An image of the oxygen molecule is attached to this answer.
This system of two oxygen atoms joined together in a covalent bond is called an oxygen molecule(O2).
Explain how an aqueous acidic solution differs from an aqueous basic solution according to the Arrhenius theory for acids and bases
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Answer:
An Arrhenius acid is a substance that associates in water to form hydrogen irons (H+) In other words an acid increases the concentration of H+ ions in an aqueous solution
For each of the following questions give the name of an element from period 2 lithium to neon which matches the description elements may be used once more than once or not at all
a) an element which has atoms with a full outer shell of electrons
b) an element which exists as both diamond and graphite
c) an element that reacts vigorously with cold water
d) a soft metallic element which is stored in oil
PLEASEEE
Answers
The elements of period 2 that satisfy the descriptions are;
a) Neon
b) carbon
c) sodium
c) sodium
What is the periodic table?We know that the periodic table is an arrangement of the elements in the order of their reactivity. We know that the elements that we have are arranged into groups and periods.
The elements that are in the same group do have similar chemical properties while the elements that are in the same period do have the same number of shells. The properties of the elements in a periods tends to change across the period.
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Please help this is due soon and I’ll mark you brainiest if you can help
Answers
Answer:
I think it's either A or D I'm not sure hope that I helped you.
what are things than can circulate
Answers
What are the three major categories used to classify elements?
a Solids, liquids, gases
b Protons, neutrons, electrons
c Groups, periods, states
d Metals. non-metals, metalloids
Answers
Answer:
i think option no. " D " = " metals, non-metals, metalloids " is the correct answer.
hope this answer will help u.
have a great time
Hope this helped you!
Which organ detects stimuli from the environment and is part of the nervous system?
Group of answer choices
A. eye
B. stomach
C. heart
D. lungs
Answers
It's the eye because it's the organ of sight
High exposure to mercury is indicated by a blood level above 10 mg/L. How many mercury atoms are in a liter of blood that contains 10 mg mercury?
Answers
Answer:
3.0x10¹⁹ atoms
Explanation:
First we convert 10 mg of mercury into grams:
10 mg / 1000 = 0.01 gThen we convert 0.01 g of mercury into moles, using its molar mass:
0.01 g ÷ 200.59 g/mol = 4.99x10⁻⁵ molThen we convert moles into number of atoms, using Avogadro's number:
4.99x10⁻⁵ mol * 6.023x10²³ atoms/mol = 3.0x10¹⁹ atomsPlease Help I need to finish this by the end of the day!
Answers
Answer:
C
Explanation:
If I am not mistaken, due to the conservation of mass, whatever mass is on the side of the reactants should be the same for the product side.
This means
218.76g+53.96g = 272.72g
272.72g-266.66g = 6.06g
So the answer should be C
what is the main function of photosynthesis
Answers
Answer:
to provide food to the plant also known as glucose
What is the application of flotation
Answers
Answer:
The law of floatation is applied in all vessels which travel by waterways that include ships, submarines and ferry boats. It is also applied in some vessels which travel by air ways such as hot air balloon and air ship. Balloons of different colors and shapes are filled with lighter gas so that will float in air.
Answer:
*hot air balloon
*swimming
Explanation:
sna makatulong po:)
There are 5 moles of N20 at STP. What is the density?
Answers
Answer:
5 mole of N2O : 112 litre of N2O
5 mole of N2O : 220 g of N2O
Then,
Density = mass/ volume
= 220/112
= 1.96 g per litre
What is the empirical formula a for a compound that is 15.3% magnesium, 44.5% chlorine, and 40.2 % oxygen
Answers
Answer:
[tex]MgCl_{2} O_{4}[/tex]
Explanation:
When calculating an empirical formula from percentages, assume you have a 100g sample. This allows you to convert the percentages directly to grams, because X % of 100g is X grams.
So:
15.3 % = 15.3g Mg, 44.5% = 44.5g Cl, 40.2% = 40.2g O
The next step is to divide each mass by their molar mass to convert your grams to moles.
15.3/24.3 = .630 mol
44.5/35.5 = 1.25 mol
40.2/16.0 = 2.5 mol
Then you will divide all of your mol values by the SMALLEST number of moles. This gives you whole numbers that are the mole ratio (subscripts) of the empirical formula.
.630 mol/.630mol = 1
1.25 mol/.630mol = 2
2.5 mol/.630mol = 4
So the empirical formula is
[tex]MgCl_{2} O_{4}[/tex]
A tank contains helium gas at 585 mmHg, nitrogen gas at 0.76 atm, and neon at 940 torr. What is the total pressure
Answers
Answer:
2.77 atm
Explanation:
The total pressure of a mixture of gases is calculated as the addition of the partial pressures of the gases. In this case, the total pressure (Pt) is calculated from the partial pressures of helium (PHe), nitrogen (PN₂) and neon (PNe):
Pt = PHe + PN₂ + PNe
First, we have to convert the partial pressures to the same unit (atm). For this, we have to know that 1 atm=760 mmHg=760 Torr
PHe = 585 mmHg x 1 atm/760 mmHg = 0.77 atm
PN₂= 0.76 atm
PNe= 940 Torr x 1 atm/760 Torr = 1.24 atm
Finally, we calculate the total pressure in atm:
Pt = 0.77 atm + 0.76 atm + 1.24 atm= 2.77 atm
Please help will mark brainliest!! What is the main point of paragraph 3?
Answers
Answer:
the highest frequency
Explanation:
how do i break my leg
Answers
Answer:
why would u want 2?
Explain in the comments why.
Explain why the temperature of the water decreased when the cold water was added to the hot water
Answers
Answer:
The water is clearly close to boiling temperature when you add the ice. So, initially the ice cools the water that is near it to near 0degC. Water between about 0 and 8 degrees is more dense than hotter water, so the cold water sinks to the bottom.Jun 14, 2020
Hope this helps if so don't hesitate to 'Thanks' and/or 'brainliest' this answer!
Answer:
hot water has more melting point
Explanation:
hot water has more melting point
hot water cpyld be boiled
Directions Identify the reactants and product in the following reaction.
4A1+302 → 2A1203
Answers
Product: 2A12O3
Many angiosperms rely on animals for
A fertilization
B pollination
C photosynthesis
D transpiration
Answers
Explanation: Many angiosperms rely on animals for POLLINATION and seeds to produce.
A student titrates an unknown weak acid, HA, to a pale pink phenolphthalein endpoint with 25.0 mL of 0.100 M NaOH. The student then titrates in 11.0 mL of 0.100 M HCl to the solution containing the neutralized unknown acid (HCl was delivered from a second buret). The pH of the resulting solution is pH
Answers
Answer:
Hello your question is incomplete the pH of the solution is unknown hence I will take the pH of the solution be = 4.7
answer : Pka = 5 i.e. > 4.7
Explanation:
Student titrates :
Unknown weak acid ( HA ) with 25 mL of 0.100 M of NaOH ( to a pale pink phenolphthalein endpoint ) then titrates with 11.0 mL of 0.100 M HCL to the solution that contains neutralized unknown acid
Assuming pH of solution = 4.7
HA + NaOH --------> H2O + NaA
at equilibrium point
0.1 * 25 * 1 = n * 1 ∴ [tex]n_{ha}[/tex] = 2.5 mmoles ------ 1
also
[tex]A^-[/tex] + HCL ---------> HA + C[tex]L^-[/tex]
at equilibrium point
[tex]n_{a}[/tex] = 1.1 mmoles --------- 2
The ratio of reaction 2 to 1
[tex]\frac{n_{a} }{n_{ha} }[/tex] = 1.1 / 2.5 ≈ 1/2 ( this show that when the pH = 4.7 approximately half of the A^- have been converted to HA )
Determine the pKa value of the solution
Given that
pH = Pka + log ( A^- / hA )
4.7 = Pka + log ( 1/2 )
therefore Pka = 4.7 - ( -0.3 ) = 5
Students in a science class learn that groundwater is an important
source of drinking water for many communities. They construct a model
to study how leaking chemicals from a landfill can affect groundwater.
What is the most effective way for the students to see how leaking
chemicals from a landfill can enter a well?
Select one:
A: Pump water out of the well to see how stained water from the tissue paper
moves toward the well.
B: Drop food color into the well at the well's opening.
C: Tear some of the colored tissue paper and put the paper pieces into the well at
the well's opening
D: Tilt the tank towards the well and drain some of the water out of the tank.
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How are plate tectonics and the rock cycle connected
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Answer:
All igneous rocks the basis of the rock cycle are formed by plate tectonics. ... The heat from the mantle that fuels plate tectonics causes both igneous and sedimentary rocks to be turned into metamorphic rocks. The metamorphic rocks can be eroded into sedimentary rocks are remelted back into igneous.
Explanation:
Help quickly pleaaas
Answers
Answer:
chymotrypsin, cleaves peptide bonds selectively on the carboxylterminal side of the large hydrophobic amino acids such as tryptophan, tyrosine, phenylalanine, and methionine
Under certain conditions butane reacts with oxygen to form butanone which can be easily hydrogenated to butanol. Butene is easily made from butanol by elimination of water.
Explanation:
These are for the first too
Pl help it’s for a grade and I can’t find it
Answers
Answer:
personally I think it's a but it could also be D.
But yeah personally I would say A
how do i make chrystals using home suppplies
Answers
You could use sodium accetate a put it in water...
A wildfire destroys most of the plant life in a forest. What would most likely happen to the animals that lived in the forest?
Answers
Answer:
They would be pushed out and lose their homes
Explanation:
A wildfire destroys most of the plant life in a forest. Animals would be pushed out and lose their homes.
What is wildfire?An unplanned, uncontrolled, and unpredictable fire inside an area of flammable vegetation is known by several names, including wildfire, bushfire, bushfire, wildland fire, and rural fire. A wildfire may be more precisely referred to by the terms bushfire, desert fire, forest fire, hill fire, peatland fire, prairie fire, vegetable fire, or veld fire, depending on the kind of vegetation that is present.
Wildfires are separate from controlled and prescribed burning, which is a good human use of wildland fire, even though controlled burns have the potential to turn into wildfires. Wildfires likely started shortly after terrestrial plants first appeared, which occurred in the Silurian epoch 419 million years ago, according to fossil charcoal. A wildfire destroys most of the plant life in a forest. Animals would be pushed out and lose their homes.
Therefore, animals would be pushed out and lose their homes.
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