Answer:
B
Explanation:
A plant cell has a cell membrane and a cell wall
what are salt properties of matter?
Answer: Salt is a chemical compound with a number of interesting properties: Crystals or white crystalline powder. Transparent and colourless in crystalline form – rather like ice. Crystallises in the isometric system, usually in the form of cubes.
Answer:
Salt is a chemical compound with a number of interesting properties: Crystals or white crystalline powder. Transparent and colourless in crystalline form – rather like ice. Crystallises in the isometric system, usually in the form of cubes.
Explanation:
give the first answer brainliest, im just fixing thier spelling
(b) Which solution has a higher percent ionization of the acid, a 0.10M solution of HC2H3O2(aq) or a 0.010M solution of HC2H3O2(aq) ? Justify your answer including the calculation of percent ionization for each solution.
Answer: The percent ionization is higher for 0.010 M solution of [tex]HC_2H_3O_2[/tex]
Explanation:
[tex]HC_2H_3O_2\rightarrow H^+C_2H_3O_2^-[/tex]
cM 0M 0M
[tex]c-c\alpha[/tex] [tex]c\alpha[/tex] [tex]c\alpha[/tex]
So dissociation constant will be:
[tex]K_a=\frac{(c\alpha)^{2}}{c-c\alpha}[/tex]
a) Given c= 0.10 M and [tex]\alpha[/tex] = ?
[tex]K_a=1.8\times 10^{-5}[/tex]
Putting in the values we get:
[tex]1.8\times 10^{-5}=\frac{(0.10\times \alpha)^2}{(0.10-0.10\times \alpha)}[/tex]
[tex](\alpha)=0.013[/tex]
[tex]\%(\alpha)=0.013\times 100=1.3\%[/tex]
b) Given c= 0.010 M and [tex]\alpha[/tex] = ?
[tex]K_a=1.8\times 10^{-5}[/tex]
Putting in the values we get:
[tex]1.8\times 10^{-5}=\frac{(0.010\times \alpha)^2}{(0.010-0.010\times \alpha)}[/tex]
[tex](\alpha)=0.041[/tex]
[tex]\%(\alpha)=0.041\times 100=4.1\%[/tex]
The percent ionization is higher for 0.010 M solution of [tex]HC_2H_3O_2[/tex]
Frankie earns $5 each time he babysits his little sister. He has saved $30. Frankie wants to save $52 to buy a new skateboard. How many more times will Frankie need to babysit to have enough money to buy the skateboard?
Answer:
52- the 30 he has already = $22
22/5= 4.4
he will have to babysit 5 times
What is the ratio of oxygen to carbon dioxide? 2 C2H6+7 O2=6 H2O+4CO2
Answer:
7:4
Explanation:
The coefficients of a balanced chemical equation give us the mole ratios. The coefficient of carbon dioxide here is 4 and oygen is 7.
During a lab activity students were given samples of four different unknown elements. The students record their observations as shown in the table
Answer:
It is Sample 3, so C
Explanation:
This is because most metals would be solid but this is probualy mercury and it has a pretty low boiling point, and all the other samples are either weak/break easily with a hammer which metals dont do that, and theres a gas, obviously not so if you use process of elimation and common sense, its C
When does the object change direction?
Distance vs. Time
50
40
30
20
10
c
D
2
6
8
10
Time
F
Answer:
50distance and 10minutes time
Explanation:
because it's the best object
Which of these pure substances do you think are Elements?
Au (Gold)
C6H12O6 (Sugar)
Fe (Iron)
NaCl (Salt)
O (Oxygen)
Fe2O3 (Rust)
What is the concentration of a solution with a volume of 2.50 liters containing 630. grams of calcium phosphate, Ca3(PO4)2?
Answer:
L=0.85M
Explanation:
ca3 (po4)
66gX1mol/310.18g=2.2178mol/2.5
Which of the following pairs of substances form a buffer system for human blood?
A.
HCl and Cl-
B.
NH3 and NH2-
C.
H3C6H5O7 and HC6H5O72-
D.
H2CO3 and HCO3-
Answer:
d. Because those chemicals are easily made when CO2 reacts with water, forming H2CO3 (via carbonic anhydrase
The pairs of substances form a buffer system for human blood is carbonic acid (H₂CO₃) and bicarbonate anion (HCO₃⁻) , Option D
What is a Buffer Solution ?
A buffer is a combination of a weak acid (or base) and a salt that contains the conjugate of that weak acid or base.
A buffer solution is added to maintain the pH of any solution
The buffer of carbonic acid (H₂CO₃) and bicarbonate anion (HCO₃⁻) is used to maintain the balance of acid and base in the body.
It is used to maintain the pH level of the body between 7.35 and 7.45 , as the pH level higher than 7.8 and lower than 6.8 can lead to death.
Therefore the pairs of substances form a buffer system for human blood is carbonic acid (H₂CO₃) and bicarbonate anion (HCO₃⁻) , Option D
To know more about Buffer Solution
https://brainly.com/question/24262133
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what do scientists use to deterimine the temperature of a star
Pls help i have no clue what the right answers are
science question. Can you also tell me what weight has to do with the acceleration?
Can someone help its confusing
Answer:
It's a metaphor. It's comparing Jordan and their emotions to a tornado
What is the percent by mass of iron in FeCl 3 ?
Answer:
34.429%
Explanation:
6. How many planets are in the solar system?
Answer:
8
Explanation:
Rocky planets:
Mercury
Venus
Earth (We are here)
Mars
Gas giants:
Jupiter
Saturn
Uranus
Neptune
Hi!there are 8 planets in the solar system they are=
MercuryVenusEarthMarsSaturnJupiterUranusNeptune(there was one more planet Pluto but in 2006 scientists said that Pluto was not a planet but a drawf planet)
The volume of Mars is more than three times as large as Mercury's.
Answer:
Ye,,it is true that Mars is bigger than mercury.
Explanation:
Actually,Mercury is the smallest planet in the solar system.
What phase change occurs when a solid changes into a gas?
Answer:
Sublimation
Explanation:
Sublimation is the term used to describe when a solid "skips" the liquid phase and turns directly into a gas from solid form. Dry ice demonstrates sublimation when exposed to room temperature air.
Pls, Answer ASAP!!!! I have to turn in my HW in 20 mins!!
In the rocket fuel formulation for NASA, 325 grams of solid aluminum (Al) particles are heated with 211 grams of solid iron III oxide (Fe2O3). Show all work and units. Include significant figures in your final answer.
a) Write the balanced equation
b) Calculate the mass of iron produced from the reaction
c) Identify the limiting reagent
d) Determine the amount of excess reactant leftover
Show all work and units. Include significant figures in your final answer.
Answer:
B. Calculate the mass of iron produced from the reaction
Explanation:
Sana makatulong mark me as a brainliest
What would the molarity of a solution be if you took 10 mL of a 13 m stock solution and made it 300 mL solution
Answer:
0.43 M
Explanation:
Use the dilution equation: M1V1 = M2V2
M1 = 13 M
V1 = 10 mL
M2 = ?
V2 = 300 mL
Solve for M2 --> M2 = M1V1/V2
M2 = (13 M)(10 mL) / (300 mL) = 0.43 M
Which element is the first element in group 13 of the periodic table of elements?
Answer:
Boron
Explanation:
Answer:
Boron
Explanation:
Boron is the first element of Group 13 and is the only metalloid of the group. Its chemical symbol is B, and it has an atomic number of 5. Boron has the electron configuration [He] 2s 2 2p 1 and prefers an oxidation state of +3. Boron has no natural elemental form; it forms compounds which are abundant in the Earth's crust.
5. Which set of coefficients will balance this chemical
equation?
_C2H4(g) +
O2(g) → 2CO2(g) + 2H2O(g)
A. 1.2
B. 1.3
C. 2.3
D. 2.5
Answer: The answer is B 1,3
Which of the following (H+) values describes a neutral solution?
O 10-1M
O 10-7M
10-14 M
O 10-12M
Answer:10-^7M
Explanation: this is a neutral solution as the [H+] and [OH-] is of same value ie,10-^7M
About what percent of the Earth is covered in salt water oceans?
A.84%
B.71%
C.49%
D.65%
Answer:
B
Explanation:
How do heatwaves show physical and chemical changes
Answer:
An example of heatwaves showing physical and chemical change is with a burning candle, when a candle burns, there is both a physical and chemical reaction.
The physical change is quite obvious and in fact, it can be seen. When the candle burns, the wax slowly melts and the candle gets smaller and smaller. This wax, as can be seen, will drip onto the candle and stick to it. When this wax forms back into a solid and stays on the candle, that is another physical change that can occur.
The chemical reaction can be a little less obvious. The first is that the heat produced by the candle consumes both the oxygen around it, as well as the fuels coming from the flame. This will then lead to carbon dioxide emissions produced by the flame, which by the way should never be inhaled. This is the chemical change that takes place in the reaction.
Use the information and table to answer the following question.
Scientists use either a melting år freezing point apparatus to determine the melting points of the following unknown compounds as part of
their investigation. Based on the melting points, the scientists determine the bond type and record the results in the table as shown.
Unknown Compound
Compound 1
Exhibits
Compound 2
Compound 3
Compound 4
Melting Point
772°C
17°C
960°C
-56°C
Which statement correctly identifies the ionic compounds and why?
A Compounds 1 and 3 are lonic. Because covalent compounds are composed of oppositely charged ions that are attracted to one
another, they require more energy to melt than ionic bonds.
O B. Compounds 2 and 4 are ionic. Because covalent compounds are composed of oppositely charged ions that are attracted to one
another, they require more energy to melt than ionic bonds.
C. Compounds 2 and 4 are ionic. Because ionic compounds are composed of oppositely charged ions that are attracted to one another,
they require more energy to melt than covalent bonds,
D. Compounds 1 and 3 are ionic. Because ionic compounds are composed of oppositely charged ions that are attracted to one another,
they require more energy to melt than covalent bonds.
Answer:
Explanation:
are you doing your mid term?well i got c
Answer:
D
Explanation:
Compounds 1 and 3 are lonic.Because ionic compounds are composed of oppositely charged ions that are attracted to one another,
they require more energy to melt than covalent bonds. just usign he process of elimination you get rid of A and B becuase covalant compound contaIN same negatively charged particles that contain requrie less energy to melt and since two and four have low melting point its d
The following equation represents the combustion of
propane in excess oxygen.
C³h⁸ + 5O²----> 3CO² + 4H²O
What is the volume of carbon dioxide gas produced
when 48 cm of propane is completely burnt
a.28 cm³
b.48 cm³
c.96 cm³
d.144cm³
Answer:
i don't know the answer now please sorry for the day before the end of the following is Open you have a good time with the button in the top right of
Answer:
3*0.35L = 1.05L
Explanation:
For part A, we need the ratio of moles of propane to moles of oxygen to get the volume of oxygen required.
The equation tells us there are 5 moles of oxygen gas required to combust 1 mole of propane.
So the required volume of oxygen is 5*0.35L = 1.75L
The equation also tells us that 3 moles of carbon dioxide are produced from the combustion of one mole of propane.
Therefore the produced volume of carbon dioxide is 3*0.35L = 1.05L
The boiling point of a liquid is the temperature at which its ____________ _____________ is equal to ____________ ____________.(atmospheric pressure, vapor pressure
Answer:
vapor pressure, atmospheric pressure
Explanation:
the boiling point of a liquid is the temperature at which its vapor pressure is equal to the pressure of the gas above it.
(I'm not too sure if this is right but I think it is)
Which of the following is an
example of cohesion?
Answer:
Explanation:
intrusive igneous rock forms when the cooling of magma takes place fast on the top of the Earth's surface. A. True B. False
Answer:
A
Explanation:
True igneous rock forms cooling of magma fast on the top
Answer:
The answer is A. True
Explanation:
According to the graph, what is the volume of the gas when the pressure is 150 kPa?
Answer:
Option (2)
Explanation:
Boyle's states that at constant temperature, volume of a gas is inversely proportional to the pressure exerted by the gas.
In other words, at constant temperature, multiplication of pressure and volume of the gas is constant.
PV = k
Here 'k' = constant
From the graph attached,
[tex](V_3,P_3)[/tex] represents (0.5, 200).
0.5 × 200 = k
k = 100
For pressure 'P' = 150 kPa
150 × V = 100
V = [tex]\frac{100}{150}[/tex]
V = 0.67 L
Option (2) is the answer.
Answer:
2 is the right answer so be it