Answer: A catalyst is a substance that speeds up the rate of a chemical reaction without being used up and remains chemically unchanged itself .
Explanation: For a reaction to take place the particles must collide with enough energy for bonds to break and reaction to occur .
BUT when a catalyst is present the reactants are able to react in a way that requires less energy ,leading to more successful collision so the reaction speeds up without the chemical composition of the catalyst being affected
NOTE: the catalyst must be chosen to suit the particular reaction
HOPE THIS HELPS IF YOU NEED MORE EXAMPLES FEEL FREE TO COMMENT IN THE COMMENT SECTION
3. An atom
OF
elemente A has mass number 39 and 19 protons
Write the electron arrangement of the atom
Answer:
Explanation:
Potassium (K) atom has 19 electrons. The full electron configuration of Potassium (K) is 1s22s22p63s23p64s1
Principal energy level
Quantum number: n
1
2
3
4
5
6
Sublevels
availableQuantum number: l
1s
2s 2p
3s 3p 3d
4s 4p 4d 4f
5s 5p 5d 5f 5g
6s 6p 6d 6f 6g 6h
Suppose you had a valuable collection of small diamonds, which you kept safe from the thieves by mixing them with white sugar crystals. You store the mixture in a jar labeled 'sugar'. Now you want to sell the diamonds. Describe how you would separate all the diamonds from the sugar.
Answer:
Pour the sugar/diamond mixture into a container of water and stir until the sugar is dissolved completely. Then strain the mixture and wash the diamonds with water.
Answer:
Stir with a large enough volume of cold water to dissolve all the sugar. Filter to leave the diamonds on the filter paper. Wash on the filter paper with more water to remove any last traces of sugar solution. Allow to dry.
Uranium-235 and uranium-238 are different ________ of uranium
(Apx answers please)
Answer:
Isotopes
Explanation:
An isotope are the atoms of an element with similar chemical identity and number of protons but different atomic masses. This means that isotopes of an element differ from one another by their number of NEUTRONS.
For example, the uranium element possesses isotopes as follows: Uranium-235 and uranium-238. This two isotopes have the same chemical identity and number of protons/atomic no., which is 92. However, the atomic masses (235 and 238) are different.
Answer:
Isotopes
Explanation:
A new stable element with an atomic number of 120 and an atomic mass of 246 is created in a particle accelerator. Enough of this element is created to determine that it combines with chlorine in a 1:2 ratio. Element 120 should be placed in the same group as _____ on the periodic table.
Answer:
Be,Mg,Ra etc
Explanation:
It should be palced in group 2A because as it reacts with chlorine in ratio of 1:2 . It's valancy is 2 and is metal as it react with non metal donating two electrons .
one more thing it fits there orderly
Câu 9: 100 g dung dịch MgCl2 9.5 % tác dụng đủ với dung dịch KOH 5,6 % .được dung dịch A và chất rắn B. Lọc rắn B và nung đến khối lượng không đổi được chất C.
a) Viết pt .Tính khối lượng răn C
b) Tính nồng độ phân trăm của dung dịch A.
hiiiiiiiii
hiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii
Some species form social groups only with members of the same gender. For example, elephants form groups with
only females and their offspring. Once the male offspring reach a certain age, they leave the group and become
solitary.
Which is a benefit of this type of social group structure?
Explanation:
For example, elephants form groups with only females and their offspring. Once the male offspring reach a certain age, they leave the group and become solitary. Which is a benefit of this type of social group structure? A:Females do not have to compete for a mate.
relate the pH of a solution to its hydronium and hydroxyl ion concentration and its acidity or basicity
brain list if your answer is good
when ph decrease that means acidity increase
when ph increase that means basicity increase
Which of the following apply to organic compounds. Select all that apply. Organic compounds cannot be synthesized. Organic compounds contain carbon. All organic compounds are products of living things. Organic compounds can be synthesized. All compounds that contain carbon are organic.
Answer:
Organic Compounds CAN BE synthesized
Organic Compounds contain Carbon
please answer this questions soon
i will mark him or her brillient
Answer:
1)Or
d.Sublimation
2)
b.iodine is the solute and alcohol is solvent
3)
a.compostion of solute
Answer:
1) a) centrifugation
OR
b) sublimation
2) a) iodine is the solute and alcohol is solvent
3) a) concentration of soLute
PLZ HELP ME WITH MY WORK
What is a compound?
A substance that is made from two different metals
B. A substance that cannot be broken into simpler substances
C. A substance that is made using a chemical reaction
D. A substance that can be separated by physical means
Answer:
C.
Explanation:
Answer A is incorrect because a compound doesn't have to be made with only metals.
Answer B is incorrect because that is actually the definition of a pure element.
Answer C is correct because to make a compound, there has to be a chemical reaction where bonds are formed and an entirely new substance is created.
Answer D is incorrect because compounds cannot be separated by physical means.
Hope this helps :D
3. What would be the freezing point for a 5.7 molal aqueous sucrose (C12H22O) solution? The freezing
point depression constant for water = 1.86°C/m. Show your work.
Answer:
- 10.6° C
Explanation:
Given that,
In the aqueous sucrose solution,
Molality of the solution (m) = 5.7
Freezing point constant (K) = 1.86
To find,
The freezing point of the solution = ?
Method:
To find its freezing point, we will first find out if the solute demonstrates an electrolyte or not.
In case it is not, the van't Hoff factor i.e. ration of particles' concentration denoted by (i) would be taken as 1. So,
ΔT(change in temperature) = i * m * K (putting the given values)
= 1 * 5.7 * 1.86
= 10.6° C
Thus, the freezing point equals to 0 - 10.6° C = -10.6° C.
22.5 ml of a 0.200 m HBr solution was added to a 50.00 ml sample of 0.250 m sodium benzoate (NaC7H5O2). Calculate the pH. Benzoic acid has a Ka 6.30 x 10-5.
In this problem, we need to find the pH of a buffer (pH = 4.45) that is produced by the reaction of strong acids as HBr that reacts with weak bases as NaC₇H₅O₂ producing its weak acid and a salt, as follows:
HBr + NaC₇H₅O₂ → HC₇H₅O₂ + NaBr
If in the reaction, the limiting reactant is the strong acid, we will produce a buffer (The aqueous mixture of a weak acid and its strong base).
Using Henderson-Hasselbalch equation, we can find the pH of this buffer:
[tex]pH = pKa + log \frac{[NaC_7H_5O_2]}{[HC_7H_5O_2]}[/tex]
Where:
pKa is -log Ka = 4.20
[] could be taken as the moles of each species
After the reaction, the moles of HBr = Moles of HC₇H₅O₂ and the remaining moles of NaC₇H₅O₂ = Initial moles of NaC₇H₅O₂ - Moles of HBr.
Moles HBr:
22.5mL = 0.0225L * (0.200mol/L) = 4.5x10⁻³ moles HBr
Moles NaC₇H₅O₂:
50.0mL = 0.0500L * (0.250mol/L) = 0.0125 moles NaC₇H₅O₂
That means the moles after the reaction of the species of the buffer are:
Moles HC₇H₅O₂ = Moles HBr = 4.5x10⁻³ moles
Moles NaC₇H₅O₂ = 0.0125 moles - 4.5x10⁻³ moles = 8.0x10⁻³ moles
Replacing in H-H equation:
[tex]pH = 4.20+ log \frac{[8.0x10^{-3}]}{[4.5x10^{-3}]}[/tex]
pH = 4.45
Learn more about Henderson-Hasselbalch equation in:
https://brainly.com/question/13423434
Chemistry!! Help me! And explain step by step!
1st part is ure answer --> 2M
Given mass -> 58 grams
mass of NaCl -> 58.44 approx -> 58 any
moles given-> 1 moles
[tex]Molarity = \frac{moles}{vol \: in \: lts} [/tex]
[tex]Molarity = \frac{1}{0.5} = \frac{10}{5} \\Molarity = 2M[/tex]
Vitamin C is a water-soluble vitamin, so your body doesn't store it. You have to get the required amount from your diet (citrus fruits are a great source!), or you could take a daily vitamin C supplement pill. Vitamin C is ascorbic acid, so to determine how much vitamin C (acid) has been placed in each pill, you could do an acid-base titration. One vitamin C pill was dissolved in water and titrated to an endpoint by 16.00 mL of a 0.447 M solution of NaOH. How many grams of ascorbic acid were there in the pill? (MW of ascorbic acid is 176.1 /mol). Explain and show your work.
Answer:
1.26 g
Explanation:
Number of moles of ascorbic acid = concentration × volume
Concentration = 0.447 M
Volume = 16.00 mL
Number of moles = 0.447 × 16/1000
Number of moles = 7.152 × 10^-3 moles
Number of moles= mass/molar mass
Molar mass of ascorbic acid = 176.1 g/mol
Mass = 7.152 × 10^-3 moles × 176.1 g/mol
Mass = 1.26 g
how do i know if a salt is insouble or soluble?
[preparations of salts]
Answer:
by the expirement:
In which mix salt with water
can you solve this science question ⁉️
Answer:
chemical reaction between those a b c it's a reaction which occurs when heating
What is the name for the compound li2so4
Answer:
Explanation:
Lithium Sulphate
Answer:
Lithium sulfate is a white inorganic salt with the formula Li2SO4. It is the lithium salt of sulfuric acid.
what is the product of SO2+H2O.
Answer:
H2O + SO2 → H2SO3
Explanation:
H2O + SO2 → H2SO3
Answer:
l think this is the answer .
what is precipitating ???
anyone please tell me how to delete an I'd
Explanation:
Desposition of solid matter in a solution
Convert the following moles to grams :)
1. 2.4 moles sulfur
2. 1.5 moles BeI2
3. 7.5 moles C6H12O6
Answer:
3
Explanation:
sky is high and I am good.
hii pls help me to balance the equation thanksss
Explanation:
2KCLO3 (s) = 2KCl (s) + 3O2 (g)
What is the solubility of salt at 60°C if 2 gm of the salt is left behind when 7 gm of its saturated solution at that temperature dried?
a) 20
b) 40
c) 60
d) 80
40
Explanation:
because its Saturated
Potassium impart purple colour but beryllium do not impart any colour to the flame.Why?
Answer:
The electrons in beryllium and magnesium are too strongly bound to get excited by flame. Hence, these elements do not impart any color.please answer fast............
It's O2 which is oxygen....
Answer:
c. CO2 is the answer.Explanation:
Hope this helps you. Please mark as brainliest. Good Luck^_^
Do plants need soil to grow
Answer:
Not all plants do need soil to grow
Explanation:
Not all plants need soil to grow. Some just do better in soil compared to other growing mediums. What plants need are minerals and nutrients, such as nitrogen, potassium, and phosphorous. Soil is an effective way of delivering those nutrients cost-effectively. You can also use alternative delivery systems like hydroponics, aeroponics, and aquaponics to achieve the desired effect. However, these are only suitable for growing shallow-rooted plants. Plants with deep roots will always need soil, as will larger plants with spreading roots.
If oxygen causes fire to burn, why didn't the world explode when fire burns at a particular place...since oxygen is everywhere...? Explain...
Answer:
Oxygen does not burn. It is not flammable, but it is an oxidizer.
Explanation
I think you are misunderstanding what is meant by "fire burns up air". Fire does use oxygen when it burns. But it also produces carbon dioxide. An oxygen molecule has two oxygen atoms in it. Fires use this to produce carbon dioxide by adding a single carbon atom from the fire’s fuel (wood, for instance).
hope it'll help:)
Which star has the highest surface temperature
A. blue star
B. yellow star
C. white star
D. red star
Answer:
The blue star is the hottest star.
Explanation:
Red stars are cooler than the sun, with surface temperatures of 3,500 K for a bright red star and 2,500 K for a dark red star. The hottest stars are blue, with their surface temperatures falling anywhere between 10,000 K and 50,000 K
Which of the following is a scientific question you could ask about the game
of basketball?
A. Do you enjoy basketball more than volleyball?
B. Which team is this year's best?
C. Which player should be traded to another team?
D. Do teams that practice more win more games?
SUBMIT
The scientific question related to the game of basketball is option D: "Do teams that practice more win more games?"
This question is scientific because it explores a cause-and-effect relationship between practice and game outcomes. It can be investigated through empirical observation and data analysis.
To answer this question, researchers could collect data on the practice hours of different basketball teams and compare them to their corresponding game performance. Statistical analysis could be used to determine if there is a correlation between practice time and winning percentage or other performance metrics.
By examining a large sample of teams over an extended period, researchers could draw conclusions about the impact of practice on game outcomes. This scientific inquiry would contribute to the understanding of the factors that influence team success in basketball and could potentially inform training strategies and coaching techniques.
For more question on basketball
https://brainly.com/question/29505871
#SPJ8
Which of the following describes scientists?
О
A. People with only one perspective
B. People with similar personalities
C. People from different backgrounds
D. People with perfect understanding of science
which of the following will show tyndall effect ?
a. salt solution
b. copper sulphate solution
c. starch solution
d. chalk powder in water
Answer:
Starch solution
Explanation:
Colloidal solutions show tyndall effect and starch solution is a colloidal solution.
