pls Help ASAP - Calcium reacts with oxygen to produce calcium oxide. What mass of calcium oxide is produced when 10g of calcium burns?
Please show your working out.
Answer:
Mass = 14.025 g
Explanation:
Given data:
Mass of Ca burn = 10 g
Mass of calcium oxide produced = ?
Solution:
Chemical equation:
2Ca + O₂ → 2CaO
Number of moles of Ca:
Number of moles = mass /molar mass
Number of moles = 10 g/ 40 g/mol
Number of moles = 0.25 mol
now we will compare the moles of Ca and CaO
Ca : CaO
2 : 2
0.25 : 0.25
Mass of CaO;
Mass = number of moles × molar mass
Mass = 0.25 mol × 56.1 g/mol
Mass = 14.025 g
Differentiate between 4 H2O and H8O4
Answer:
How many atoms of hydrogen and oxygen are in 2 molecules of water? ... 7) Using complete sentences, explain the difference between the chemical ... (s) solid, (l) liquid, (g) gas, (aq) aqueous solution (dissolved in water).
Explanation:
hope this helps✌️
What is electrical energy?
O A. Energy stored in a molecule
B. Energy released by a temperature change
O c. The movement of electrons
O D. The sound from an explosion
What are the reactants in the reaction? What are their properties? Perform a quick Internet search, if needed.
The reactants in this reaction are sodium and chlorine. Sodium is a soft, silvery-white metal that is highly reactive. Chlorine is a poisonous greenish-yellow gas that has an odor and combines readily with other elements.
This might be the exact question so you might wanna rephrase it but good luck! :)))
A reactant is a substance that undergoes change during a chemical reaction.
A reaction in a chemical experiment is which takes place when there are mixtures between two or more reactants.
There are about four types of reactions which are:
SynthesisDecompositionSingle replacementDouble replacementPlease note that your question is not complete, therefore, i would give you a general overview to help you.
Some examples of reactants include:
HydrogenSodiumChlorine, etcRead more here:
https://brainly.com/question/12056938
What happened when you placed your bottle system
in cold water?
Answer:
The water level in the pipe went down.] ... [The hot water in the cup heated up the water particles inside the bottle. They began to move more. Greater motion (kinetic energy) pushed the particles farther apart, resulting in expansion.
pls answer i need it now!! I will give brainliest to the best answer!!
Answer:
sample 2
Explanation:
hope this helps
When an atom is charged, it is called an ion. How many electrons are in O^2-?
Answer:
10 electrons
Explanation:
What are 3 ways you know something is living
Question 1
Organisms sharing a common ancestor
Evolutionary history
A. Fossil record
B.Anatomy
C.Common ancestry
D.Evolution
Answer:
Fossil record
Explanation:
but first think about it befor you do so it could be wrong im not a computer
When ammonium nitrate (NH4NO3) explodes, the products are nitrogen, oxygen, and water. When 50.0
grams of ammonium nitrate explode, 22.0 grams of nitrogen and 8.0 grams of oxygen form. How many
grams of water form?
Answer:
( NH4NO3 -> N2+O2+H2O)
Explanation:
40g= 14g+8g+X
x=18g
hope that helps :)
What kind of statement is," Roller coasters are the best to use of Newton's laws of motions
Answer:
An opinion.
Explanation:
In physics, Sir Isaac Newton's first law of motion is known as law of inertia and it states that, an object or a physical body in motion will continue in its state of motion at continuous velocity (the same speed and direction) or, if at rest, will remain at rest unless acted upon by an external force.
The statement, "Roller coasters are the best use of Newton's laws of motions" is an opinion because it is not based on any evidence, facts or has a proof to back it up.
In English literature, an opinion is considered to be more like a claim.
A claim can be defined as a statement that is used by a writer to prove, substantiate or support an argument. Thus, a claim is an assertive statement expressed by a writer to prove that an argument is true or real.
how many molecules are in 18moles of CH.
Answer:
1.08 x 10²⁵molecules
Explanation:
From the mole concept we know that ;
1 mole of any substance contains 6.02 x 10²³ molecules
This number is the Avogadro's number.
So;
18 mole of CH will contain:
Number of molecules of CH = 18 x 6.02 x 10²³ = 1.08 x 10²⁵molecules
The number of molecules is therefore 1.08 x 10²⁵molecules
how many grams is 5.16 mol br2?
Answer:
Mass = 824.57 g
Explanation:
Given data:
Mass of bromine = ?
Number of moles of bromine = 5.16 mol
Solution:
Formula:
Mass = number of moles × molar mass
Molar mass of bromine = 159.8 g/mol
by putting values,
Mass = 5.16 mol × 159.8 g/mol
Mass = 824.57 g
Why does your heart rate increase while exercising?
Answer:
During exercise, your body may need three or four times your normal cardiac output, because your muscles need more oxygen when you exert yourself. During exercise, your heart typically beats faster so that more blood gets out to your body.
Answer:
I'd myself say it's because a lot of people are fat but here's the real answer ;)
During exercise, your body may need three or four times your normal cardiac output, because your muscles need more oxygen when you exert yourself. During exercise, your heart typically beats faster so that more blood gets out to your body.
Sulphur is found in many forms in the nature. S2, S6 and Ss being some of them. What can we say
will certainly be common among these forms of sulphur?
(A) They will exhibit same physical properties
(B) They will exhibit same chemical properties
(C) Sulphur atoms in each will be identical
(D) All of the above
Answer:
What can be said about these common forms of sulphur is that;
(B) They will exhibit same chemical properties
Explanation:
Allotropy is the property of an element to exist in two or more forms in the same physical state
Allotropes have several similar chemical properties but differ in their physical properties, such as the white, pale yellow to totally colorless diamond and the gray graphite
Sulphur can exist in several allotropic forms, and carbon is the only element that has more allotropes than sulphur
The sulphur allotropes includes S₂, S₆, and S₅ have similar chemical properties but different physical properties.
The correct option is;
What can be said about these common forms of sulphur is that they have the same chemical properties
Can somebody Please Help
Answer:
5425440 μm
Explanation:
From the question given above,
Length (in ft) = 17.8 ft
Length (in μm) =?
Next, we shall convert 17.8 ft to in. This can be obtained as follow:
1 ft = 12 in
Therefore,
17.8 ft = 17.8 ft × 12 in / 1 ft
17.8 ft = 213.6 in
Next, we shall convert 213.6 in to cm. This can be obtained as follow:
1 in = 2.54 cm
Therefore,
213.6 in = 213.6 in × 2.54 / 1 in
213.6 in = 542.544 cm
Finally, we shall convert 542.544 cm to μm. This can be obtained as follow:
1 cm = 10⁴ μm
Therefore,
542.544 cm = 542.544 cm × 10⁴ μm / 1 cm
542.544 cm = 5425440 μm
Therefore, 17.8 ft is equivalent is equivalent to 5425440 μm
The chemical equation below shows the photosynthesis reaction.
6CO2 + 6H2O → C6H12O6 + 6O2
A reaction uses 528 g of CO2. How many grams of water are used in this reaction?
Answer:
12
Explanation:
Choose the statement below that correctly describes electrons.
a. Electrons have a positive charge and are lighter than protons
b. Electrons have a positive charge and are heavier than protons
c. Electrons have a negative charge and are heavier than protons
d. Electrons have a negative charge and are lighter than protons
Answer:
d. Electrons have a negative charge and are lighter than protons
Explanation:
The best statement that describes electrons is that electrons are negatively charged and are lighter than protons.
There are three known subatomic particles which are:
Protons which are the positively charged particles within an atom. Electrons are the negatively charged particles Neutrons do not carry any charges.The mass of the protons and neutrons are similar.
Electrons are lighter than both protons and neutrons.
Metals bond with halogens to form colorless metal halides. During an experiment, chlorine water was added to a solution of potassium bromide. A record of the experiment is shown.
Experimental Record
Reactants Color of Reactants Color of Reactants after Mixing
cl,
Colorless solution
Deep yellow-orange colored solution is formed
KBT Colorless solution
Which of the following conclusions can be made about this chemical reaction based on the data? (1 point)
O Chlorine is more reactive than bromine.
Potassium bromide and chlorine do not react.
O Potassium metal is formed from a single replacement reaction.
O Bromine solution is colorless and is formed due to a single replacement reaction.
Answer:
O Chlorine is more reactive than bromine.
Explanation:
From this experiment we can conclude that chlorine is more reactive than bromine and it is the reason why the reaction is able to proceed.
The reaction is a single displacement reaction in which the position of an element in the activity series is very important. Since chlorine is more electronegative and highly reactive when compared to bromine, it will displace bromine from the solution of potassium bromide. So, we have product of potassium chloride and the bromide.How the calculation of the [OH-], pH and % ionization for 0.619 M ammonia (NH3) NH3 + H2O (liq) rightwards harpoon over leftwards harpoon NH4+ + OH- Kb = 1.8 x 10-5
Answer:
[OH⁻] = 3.34x10⁻³M; Percent ionization = 0.54%; pH = 11.52
Explanation:
Kb of the reaction:
NH3 + H2O(l) ⇄ NH4+ + OH-
Is:
Kb = 1.8x10⁻⁵ = [NH₄⁺] [OH⁻] / [NH₃]
As all NH₄⁺ and OH⁻ comes from the same source we can write:
[NH₄⁺] = [OH⁻] = X
And as [NH₃] = 0.619M
1.8x10⁻⁵ = [X] [X] / [0.619M]
1.11x10⁻⁵ = X²
3.34x10⁻³ = X = [NH₄⁺] = [OH⁻]
[OH⁻] = 3.34x10⁻³M% ionization:
[NH₄⁺] / [NH₃] * 100 = 3.34x10⁻³M / 0.619M * 100 = 0.54%
pH:
As pOH = -log [OH-]
pOH = 2.48
pH = 14 - pOH
pH = 11.52If you start with substance A and substance B, combine them together,
and produce a new substance C, you have witnessed a
Answer:
Chemical change
Explanation:
If you start with substance A and B and you produce C, you have witnessed a chemical change and this is a synthesis or combination reaction.
A + B → C
We know this because from the two different reactants, a new substance C has been formed.
The substance C is produced via a chemical change.
In a chemical change, new kinds of products are usually formed and the reaction is not easily reversible.
The reaction of Pb+4 and O-2 produces the compound of
a
Pb2O2
b
PbO
c
Pb2O
d
PbO2
Answer:
Pb₂O₄
Explanation:
The given species are:
Pb⁴⁺ O²⁻
Now, to solve this problem, we use the combining powers which corresponds to the number of electrons usually lost or gained or shared by atoms during the course of a chemical combination.
Pb⁴⁺ O²⁻
Combining power 4 2
Exchange of valencies 2 4
Now the molecular formula is Pb₂O₄
4. Will competition for food increase or decrease carrying
capacity?*
O A. decrease
O B. increase
If two types of matter are combined and energy is given off, what type of change is likely to have occurred?
Answer:
Chemical change
Explanation:
If two types of matter reacts or are combined and energy is given off, the type of change that might have occurred is a chemical change.
A chemical change is one in which a new kind of matter is formed.
It is always accompanied by energy changes.
The process is not easily reversible.
When an exothermic reaction or change occurs, heat is released and it is a typical characteristic of chemical change.A sample of pure radioactive isotope is left to decay. After 40.0 days, the 1 point
sample is placed in a mass spectrometer, and it is determined that only
25% of the original isotope remains. How long is the half-life?
Answer:
6 months and 1 day
Explanation:
How does the number of molecules in 1 mol of oxygen compare with the number of molecules in 1 mol of nitrogen?
1 mol of oxygen has fewer molecules.
1 mol of oxygen has more molecules.
Each sample has the same number of molecules.
The molecules cannot be compared without knowing the mass.
Answer:
Each sample has the same number of molecules.
Explanation:
Just took the quiz on edge 2021
Taking into account the definition of Avogadro's number, each sample has the same number of molecules.
Avogadro's NumberAvogadro's Number or Avogadro's Constant is called the number of particles that make up a substance (usually atoms or molecules) and that can be found in the amount of one mole of said substance. Its value is 6.023×10²³ particles per mole.
Avogadro's number applies to any substance.
This caseAvogadro's number applies to any substance. This means that the number of molecules in 1 mol of oxygen is equal to the number of molecules in 1 mol of nitrogen.
Finally, the correct answer is the third option: each sample has the same number of molecules.
Learn more about Avogadro's Number:
brainly.com/question/1445383
brainly.com/question/1528951
How many moles are in 9.07 x 10^23 atoms of sodium chloride?
Answer:
1.5 moles of sodium chloride are present.
Explanation:
Given data:
Number of moles of sodium chloride = ?
Number of atoms of sodium chloride = 9.07×10²³
Solution:
The given problem will solve by using Avogadro number.
It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance. The number 6.022 × 10²³ is called Avogadro number.
1 mole = 6.022 × 10²³ atoms
9.07×10²³ atoms × 1 mol / 6.022 × 10²³ atoms
1.5 moles of sodium chloride are present.
Heating up an object can cause it to
Answer:
We know that kinetic energy is one of the forms of internal energy, so the release of heat from an object causes a decrease in the average kinetic energy of its particles.
i really need help with this question can you guys help me
Tamara pours hot tea into a cold mug. A few moments later, she picks up the mug, and it is now warm.
Answer:The Hot tea makes the mug a hot mug
Explanation:
Answer: The thermal (heat) energy in the tea, is being transferred to the mug