Answer:
C
Explanation:
The reactions:
[tex] \mathrm{Mg(NO_3)_2 \longrightarrow MgO+ 2NO_2 +O_2}\\
\mathrm{Mg(OH)_2 \longrightarrow MgO + H_2O}\\
\mathrm{MgCO_3 \longrightarrow MgO +CO_2}[/tex]
When does a solar Eclipse happen, and how?
Answer:
Solar Eclipse happens when the moon gets between the sun and the earth, the moon gets all the light and blocks the earth from getting sunlight.
Hope this helps ;) ❤❤❤
Which series represents the flow of thermal energy in a home with a refrigeration cooling system?
Inside air coolant in cooling system – outside air
X Fuel
- air inside piston chamber piston movement
Inside air
outside air
Fuel
Inside air
Answer
A is the answer
Electronic configuration is best described as
a. protons in the nucleus of atom
b. electrons on the outermost orbit
c. attraction of electrons between two atoms
d. arrangement of electrons in an atom
Answer:
d
Explanation:
The arrangement of electrons in an atom
Answer:
D. Arrangement of electrons in an atom.
Explanation:
K L M N O P Q
2 8 8 18 18 32 50
The path where electrons revolve is called orbits.
Hope his helps ;) ❤❤❤
Stars are _____
for most of their lives.
A) stable
B) unstable
C) unpredictable
Answer:
A. Stable
Explanation:
unless ur talking about the star in your PFP, then it's unstable xd
Answer:c
Explanation:
Glucose has formula C6 H12 O6.
Calculate the number of Oxygen atoms present in 18 g of glucose
Explanation:
this may help u follow me and mark as brainlist PlZzzzz
A subtance X contains 10 gram of calcium carbonate calculate the number of oxygen atom present in 10 gram of calcium carbonate
[tex] \LARGE{ \boxed{ \rm{ \purple{Required \: answer}}}}[/tex]
☃️ Chemical formulae ➝ [tex]\sf{CaCO_3}[/tex]
How to find?
For solving this question, We need to know how to find moles of solution or any substance if a certain weight is given.
[tex] \boxed{ \sf{No. \: of \: moles = \frac{given \: weight}{molecular \: weight} }}[/tex]
And, Then we need to find the number of molecules which can be found by:
[tex] \large{ \boxed{ \sf{no. \: of \: molecules = N_A \times no. \: of \: moles}}}[/tex]
Here, Na = Avagadro Number (6.022 × 10²³)
☀️ As it is a compund, We considered molecules. Then, we can predict the no. of atoms of elements in one molecule of compound and get the answer.
Solution:
Atomic weight of elements:
Ca = 40C = 12O = 16❍ Molecular weight of [tex]\sf{CaCO_3}[/tex]
= 40 + 12 + 3 × 16
= 52 + 48
= 100 g/mol
❍ Given weight: 10 g
Then, no. of moles,
⇛ No. of moles = 10 g / 100 g mol‐¹
⇛ No. of moles = 0.1 moles
☄ No. of moles of Calcium carbonate in the given weight = 0.1 moles
Finding no. of molecules,
⇛ No. of molecules of CaCO3 = 0.1 × 6.022 × 10²³
⇛ No. of molecules of CaCO3 = 6.022 × 10²²
Now,
1 molecule of [tex]\sf{CaCO_3}[/tex] = 3 atoms of Oxygen.Then, 6.022 × 10²² molecules will have,
= 3 × 6.022 × 10²² atoms of oxygen
= 18.022 × 10²² atoms of oxygen
In more scientific form,
= 1.8022 × 10²³ atoms of oxygen
☄ Hence, Final answer - 1.8022 × 10²³ atoms
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calculate the number of moles equivalent to 5.0 gram of calcium oxide
please help
Answer:
The answer is 0.089 molExplanation:
The number of moles of a substance can be found by
[tex]n = \frac{m}{M} [/tex]
where
n is the number of moles
M is the molar mass
m is the mass of the substance
To find the number of moles we must first find the molar mass
Chemical formula for calcium oxide is
CaOSo the molar mass of CaO is
M( CaO) = 40 + 16 = 56 g/mol
Mass of CaO = 5.0g
Substitute the given values into the formula
The number of moles in 5.0g of calcium oxide is
[tex]n = \frac{5 \: g}{56 g/mol} [/tex]
We have the final answer as
n = 0.089 molHope this helps you
[tex] \LARGE{ \boxed{ \pink{ \rm{Answer}}}}[/tex]
☃️ Chemical formulae ➝ [tex]\sf{CaO}[/tex]
How to find?For solving this question, We need to know how to find moles of solution or any substance if a certain weight is given.
[tex] \boxed{ \sf{No. \: of \: moles = \frac{Given \: weight}{Molecular \: weight} }}[/tex]
Solution:Atomic weight of elements:
Ca = 40O = 16❍ Molecular weight of [tex]\sf{CaO}[/tex]
= 40 + 16
= 56 g/mol
❍ Given weight: 5 g
Then, no. of moles,
⇛ No. of moles = 5 g / 56 g mol‐¹
⇛ No. of moles = 0.089 moles [tex]\approx[/tex] 0.09 moles
⚘ No. of moles of Calcium oxide in the given weight = 0.09 moles approx.
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Ice sinks in methanol, but floats on water. From this we can conclude: A The density of ice in methanol must be different from that in water. B The density of water must be less than the density of methanol. C The density of ice must be greater than the density of water. D The density of methanol must be less than the density of water.
Answer:
A
Explanation:
Density: water>ice>methanol
Ice is lighter than methanol hence it is able to float on it. However, ice is denser than water hence it sinks.
Answer:
The answer is A.
Explanation:
The density of ice in methanol must be different from that in water.
i need help asap. any help is appreciated.
the diagram shows an electrochemical cell with copper (left) and zinc (right) strips.
**Label all parts (1-9), including the solutions in each beaker and the connecting tube
**Label which cell is the cathode and which cell is the anode include the charge on each strip
**Show, or describe in detail, the flow of electrons
**Describe what type of electrochemical cell is pictured. Explain how the cell works Include the oxidation the oxidation half-reacions in your explanation
Answer:
Explanation:
1- Cathode 2- copper electrolyte solution usually (CuSO4) 3- Cu half cell 4- bulb (when lighted, shows the current is flowing) 5- Zn half cell 6- Zn electrolyte solution 7- connecting wires 8- anode (Zn) 9-salt bridge
2- the copper-(Cu) electrode is the cathode and the zinc-(Zn) electrode will be the anode. This is because the cathode is negatively charged (while Cu is positively charged, so it attracts) and the anode is positively charged (while Zn will be negative)
3- the electrons flow from the anode, where oxidization takes place, to the cathode, where reduction reactions take place.
That's the best i can do. Hope it helps.
Answer:
Explanation:
• Label all parts (1–9), including the solutions in each beaker and the connecting tube.
1. Copper strip
2. Cu2+(aq) (copper electrolyte solution or copper nitrate)
3. Cathode compartment
4. Light bulb
5. Anode compartment
6. Zn2+ (aq) (zinc electrolyte solution or zinc nitrate)
7. The connecting wires or the external circuit
8. Zinc strip
9. Salt bridge
• Label which cell is the cathode and which cell is the anode. Include the charge on each strip.
The copper strip is the cathode and the zinc strip is the anode. The anode is positively charged and the cathode is negatively charged. This is because the cathode attracts a positive charge and the anode attracts a negative charge.
• Show, or describe in detail, the flow of electrons.
The atoms from the zinc strip are oxidized into zinc ions, (the anode is where oxidation occurs). The electrons in the anode then travel through the wire to the copper strip. The electrons then merge with the copper ions in the solution creating copper metal (the cathode is where reduction occurs).
• Describe what type of electrochemical cell is pictured. Explain how the cell works. Include the oxidation and reduction half-reactions in your explanation.
This is a voltaic or galvanic cell. It works by using spontaneous oxidation-reduction reaction to generate electricity.
Zn(s) --- Zn2 + (aq) + 2e-
Cu2 + (aq) + 2e- --- Cu(s)
pls help!!
will give the brainliest
plz answer correctly
Urgent!!!
Answer:
for number 2
Explanation:
Hydrogen. Hydrogen ignites in air. If hydrogen is present in a test tube, a lighted splint held near its mouth ignites with a squeaky pop.
Examine the assumption. Assumption: The Earth is flat. Which statements accurately describe how the assumption affects scientific thinking? (Select all that apply. People think the Earth is flat, so they think that the Earth does tilt on its axis while revolving around the Sun. People think the Earth is flat, so they think that it is only safe to travel certain distances from a given location. People think the Earth is flat, so they think that when the Sun sets, it goes underneath the Earth. People think the Earth is flat, so they think that when traveling in a straight line, there is no end.
Answer:
The statements that accurately describe how the assumptions affects scientific thinking are;
People think that the Earth is flat, so they think that it is only safe to travel certain distances from a given location.
People think that the Earth is flat, so think that when the Sun sets, it does underneath the Earth
Explanation:
The proof that the Earth is round was made by the Greek philosopher, Aristotle, over 2,000 years ago, by observation of the change in the constellation of the stars as a person changes his position North or South
The initial belief was that the Earth is flat disc surrounded by water, while the it was believed that the shape of the Earth was that of a square with four mountains at the vertices that support the sky from falling.
Which of these is the definition of the EXPLODE Physical Hazard?
A) Chemicals that are likely to be flammable and/or support a fire
B) Chemicals that release high pressure and could cause bodily injury
C) This is a potential reaction that could take place when two chemicals are
mixed together.
D) This is when a chemical breaks down and could become harmful when
handled improperly or exposed to extreme temperatures
Answer:
Explanation:
Physical hazard means a chemical for which there is scientifically valid evidence that it is a combustible liquid, a compressed gas, explosive, flammable, an organic peroxide, an oxidizer, pyrophoric, unstable (reactive) or water-reactive.
EXPLODE:
to expand with force and noise because of rapid chemical change or decomposition, as gunpowder or nitroglycerine (opposed to implode).
to burst, fly into pieces, or break up violently with a loud report, as a boiler from excessive pressure of steam.
are mountains physical or chemical property
Is water a physical or chemical property
is a box a physical or chemical property
is a lion a physical or chemical property
Answer:
Answer: mountains not sure
Water is chemical
Box is physical
Lion is physical
Hope this helped!!
Explanation:
What must happen for water to boil at a given pressure?
O A. The water molecules must become more orderly.
O B. The water must gain thermal energy from its surroundings.
O C. The average kinetic energy of the water molecules must decrease.
D. The water must give off thermal energy to its surroundings.
Answer:
B. The water must gain thermal energy from its surroundings.
Explanation:
Boiling is the process whereby a substance is changed from a liquid state to a gaseous state due to the application of heat. For boiling to be achieved, a liquid substance must reach or exceed its boiling point, which is the specific temperature at which a specific liquid boils.
For this change of state i.e. from liquid to gas, to occur, atoms or molecules of the liquid must gain kinetic energy and move faster. However, this kinetic energy cannot be attained without a rise in temperature, which causes the molecules to gain THERMAL ENERGY or heat energy and move fast. Thermal energy is the energy that arises from a hot substance.
Therefore, for water to boil at a given pressure, it must gain thermal energy from its external surroundings, which causes its molecules to have an increased kinetic energy and move faster. This fast movement of the molecules causes the transition of phases (from liquid to gas).
(Pls Help) The study of such concepts as motion, force,y energy, matter, heat, sound, light, and the components of atoms is:
- Physics
- Biology
- Earth Science
- Astronomy
Answer:
It is Physics
because these are all physical components and/or characteristics
-Biology is the study of life
-Earth science is the study of the biosphere we live in
-Astronomy is about space
Answer:
Physics
Explanation:
Physics is the study of motion and force...
Biology is the study of life
Earth Science is wind, water and uk...
Astronomy is about planets and stars
What is the molar mas of zinc (Zn)? 6.02 g/mol 30.0 g/mol 48.7 g/mol 65.38 g/mol
Molar mass is defined by the ratio of the mass to the moles. The molar mass of zinc (Zn) in the periodic table is said to be 65.38 g/mol. Thus, option D is correct.
What is molar mass?Molar mass is the mass of the element or the compound in one mole of the given substance. It is denoted in units gm/ mol. The units come from the ratio of mass in grams to the moles in mol.
It is used to calculate the amount of the substance present in the mole of the substance and can be expressed as particles, like ions, or molecules with the help of Avogadro's number.
The molar mass or the atomic mass of the zinc element is denoted in the periodic table. The mass is written on the lower side of the element symbol.
Therefore, the molar mass of zinc (Zn) is 65.38 g/mol.
Learn more about molar mass here:
https://brainly.com/question/27669728
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What do you mean by the ’4R principle’ to develop environment friendly habits?
Answer:
We mean this by '4R principle'
ReduceReuseRecucleThe question may be about ' 3R' principle....
How can you guess the name of the element using the chemical formula ?
The number of protons define what element we're dealing with.
Answer: The number of protons define what element we're dealing with.
Explain what a limiting reactant is and describe the process to determine the limiting reactant in the example listed below: Given 3.4 grams of x compound with a molar mass of 85 g and 4.2 grams of y compound with a molar mass of 48 g How much of compound xy can be generated 2x + y2 = 2xy
Answer:
4.36g XY
I hope it helps!
The lock-and-key mechanism refers to
the complementary shapes of an enzyme and a substrate.
the attractive forces between an enzyme and a substrate.
the ability of an enzyme to lower the activation energy of a reaction.
the ability of an enzyme to "unlock" the products of a reaction.
Answer:
A). The complementary shapes of an enzyme and a substrate.
Explanation:
The Lock-and-key mechanism was proposed by Emil Fischer for the first time and characterized as the metaphor which helps in elucidating the specificity of the enzymatic reactions. In this metaphor, the lock is described as the enzyme while 'key' is characterized as the substrate which the enzyme acts upon. If the key is not appropriately sized, it will not fit into the active site i.e. the keyhole of the lock or enzyme and reaction will not take place. Thus, option A is the correct answer.
