Answer:
(1) breaking a pencil (2) rusting of iron
Explanation:
breaking a pencil does not alter the chemical properties of the pencil, it merely breaks it into 2 while the rusting of iron is changing the properties chemically because the iron is oxidizing and reacting with the water and oxygen in the atmosphere
What foods have peroxides?
Answer: Wheat flour, edible oil, egg white, lettuce preservative, meat or poultry marinade, vegetable antibacterial wash.
Explanation:
hydrogen peroxide is used as a bleaching agent in some food
I hope this helped
Assuming constant pressure, rank these reactions from most energy released by the system to most energy absorbed by the system, based on the following descriptions:__________.
A: Surroundings get colder and the system decreases in volume.
B: Surroundings get hotter and the system expands in volume.
C: Surroundings get hotter and the system decreases in volume.
D: Surroundings get hotter and the system does not change in volume.
Answer:
C: The surroundings heat up and the system decreases in volume.
D: The surroundings heat up and the system does not change volume.
B: The surroundings heat up and the system expands in volume.
A: The surroundings get cold and the system decreases in volume.
Explanation:
The most exothermic reactions are those that release heat, that is to say, they give up the heat as it cools and the surroundings heat up.
As for endothermics, that is, those that absorb or capture the heat of the medium, they are variables that cool the environment that surrounds them and increase their internal temperature
Which of the following is an example of a behavioral trait that
is likely to increase reproductive success?
O colorful feathers
O a dance
O tail length
Answer:
The answer is option A
Colorful feathers
Hope this helps you
define noble gases ?
Answer:
The noble gases are the chemical elements in group 18 of the periodic table. They are the most stable due to having the maximum number of valence electrons their outer shell can hold. Therefore they rarely react with other elements since they are already stable
Which statement describes how the Van Allen belts are formed? O when low-energy particles from the Sun bounce off Earth’s magnetic field O when high-energy particles from the Sun bounce off Earth’s magnetic field O when low-energy particles from the Sun are trapped by Earth’s magnetic field O when high-energy particles from the Sun are trapped by Earth’s magnetic field (Earth/Space Science)
Answer:
when high-energy particles from the sun are trapped by earth's magnetic field
Explanation:
it is produced by a "depression" in the Earth's magnetic field in that area, caused by the fact that the center of the Earth's magnetic field is deviated from its geographic center by 450 km. Such an anomaly is thought by some to be a side effect of a Geomagnetic Reversal. These radiation belts originate from the Earth's intense magnetic field that is the product of their rotation. That field traps charged particles (plasma) from the Sun (solar wind), as well as charged particles that are generated by interaction of the Earth's atmosphere with cosmic radiation and high-energy solar radiation.
Answer:
D
Explanation:
its the last one
How much oxygen will contain the same number of atoms as the number of molecules in 73 g of HCI?
Answer:
64g of O2.
Explanation:
We'll begin by calculating the number of molecules in 73g if HCl.
This is illustrated below:
From Avogadro's hypothesis, we understood that 1 mole of any substance contains 6.02×10²³ molecules. This implies that 1 mole of HCl also contains 6.02×10²³ molecules
1 mole of HCl = 1 + 35.5 = 36.5g
Thus, if 36.5g of HCl contains 6.02×10²³ molecules, then 73g of HCl will contain = (73 x 6.02×10²³)/36.5 = 1.204×10²⁴ molecules.
Therefore, 73g of HCl will contains 1.204×10²⁴ molecules.
Now, we shall determine the mass of oxygen that will contain 1.204×10²⁴ molecules.
This can be obtained as follow:
1 mole of O2 = 16x2 = 32g
32g of O2 contains 6.02×10²³ molecules.
Therefore, Xg of O2 will contain 1.204×10²⁴ molecules i.e
Xg of O2 = (32 x 1.204×10²⁴)/6.02×10²³
Xg of O2 = 64g
Therefore, 64g of O2 will contain the same number of molecules (i.e 1.204×10²⁴ molecules) in 73g of HCl.
(7) Give two examples of solid poeciption
differentiate between parallel circuit and series circuit
Answer:
series means current same
parallel means potential same
Silver is composed of a single type of atom and cannot be broken down into different substances. Silver is an example of a(n)
ОА.
element
ОВ.
compound
molecule
Explain the methods of passive transport that move molecules across the plasma membrane of the cell.
(4 marks)
A farmer distributed his cabbages as follows: A certain hospital received a quarter of the
total number of bags. A nearby school received half of the remainder. A green grocer
received a third of what the school received. What remained were six bags more than
what the green grocer received. How many bags of cabbages did the farmer have?
(3
Answer:
Explanation:
Let the farmer had n no of bags of cabbage .
given to hospital = n / 4
given to school = 1/2 x 3n /4
= 3n / 8
given to grocer = 1 / 3 x (3n / 8 )
= n / 8
No of bags distributed
= n / 4 + 3n / 8 + n / 8
= 6n / 8
Remaining bag
= n - 6n / 8
= 2n / 8
According to question
2n / 8 = 6 + n / 8
n / 8 = 6
n = 48 .
how can a mixture of salt and sand be seperated
Answer:
filtration
Explanation:
1.put the mixture in a beaker
2.add water to the beaker and stir to dissolve salt
3.filter using a filter paper to have sand as the residue
4.Evaporate the water to remain with salt crystals
A perfume bottle is dropped in the comer of a room. The odor of the perfume can be detected on the other side of the statement best describes this observation? Particles are moving from regions of high concentration to low concentration.Particles are moving from regions of low concentration to high concentration. Particles are moving through a small opening into a smaller volume. Particles are moving through a small opening into a larger volume.
Answer:
Particles are moving from regions of high concentration to low concentration.
hope this answer correct (^^)
Answer:
A. Particles are moving from regions of high concentration to low concentration.
Explanation:
took a test
What is Rutherford atomic modle
Answer:
Rutherford's atomic model explained how the electrons surrounded the nucleus of protons and neutrons. His model showed how J. J. Thomson's Plum Pudding model was incorrect.
Answer:Rutherford model of an atom shows that an atom is mostly an empty space,with electrons orbiting a fixed positively charged nucleus in set.
Explanation:
Please help, I don't under stand! Balance the following oxidation-reduction reaction and indicate which atoms have undergone oxidation and reduction. ____FeCl3 + ____H2S Imported Asset ____FeCl2 + ____S + ____HCl
Answer:
3 FeCl3 + H2S = 2 FeCl2 + S + 2 HCl
Explanation:
Fe goes form +3 to +2
S goes from -2 to 0
H and Cl are spectator ions
Fe3+ + 1e-= Fe2+
H2S = S + 2 H+ + 2e-
3 Fe3+ + H2S = 2 Fe2+ + S + 2 H+
3 FeCl3 + H2S = 2 FeCl2 + S + 2 HCl
1. The atomic number of an element is 23 and its mass number is 56.
a. How many protons and electrons does an atom of this element have?
b. How many neutrons does this atom have?
Answer:
23 protons, 23 electrons, 33 neutrons
Explanation:
I don't know why my answer got deleted but no worries, I can answer again. The number of protons and electrons is equal to the atomic number which is 23 and the number of neutrons is 56 - 23 = 33 because atomic mass denotes the number of protons and neutrons.
Research to find out 5 uses of magnets in our daily life in medical contexts, route finding, security, sorting steel from other materials for recycling, etc.
Answer:
Medical: Magnets are used for the RMN, which uses waves and magnets to create images of the body, this process is really complex because is deeply related to quantum mechanics, so i will not dive in the topic.
Security: You can attach a magneto to a sensor, and when the magnet detects a metal, a current flows to the sensor and it can make a noise. This system is used to detect if someone has something of metal (like a knife for example) and a similar system is used to detect land mines or metals under the ground, which can be related to "route finding".
Sorting steel: When you have a mix of different metals, some of them will be attracted to the magnet and others not. An example where this is used is when you have a piece of steel with impurities, you can melt it and use a magnet to only grab the steel and leave most of the impurities.
Recycling. Big magnets are used to manage large pieces of steel that may be difficult or dangerous to handle by hand, for example. in order to move old cars and objects of similar size of steel, a big magnet is used.
Music: Modern instruments like electric guitars or electric basses, use magnets in the pickups: The magnet detects the movement of the strings, and this creates a current in a copper wire that is winded around the magnets, and that current then is transformed into sound by the amplifier.
What characteristics determine how easily two substances change temperature? Check all that apply.
volume of the two substances in contact
amount of time the two substances are in contact
area in contact between the two substances
specific heat of the material that makes up the substances
Odensity of the two substances in contact
amount of time the two substances are in contact. area in contact between the two substances. specific heat of the material that makes up the substances. the density of the two substances in contact.
The characteristics determine how easily two substances change temperature is amount of time the two substances are in contact, area of contact between the two substances, specific heat of the material that makes up the substances and the density of the two substances in contact. Therefore, option B, C, D and E are correct.
When two substances have different temperatures come into contact?When two substances that have different surface temperatures come in contact, conduction happens. The substance with the higher temperature always transfers energy to the one with the lower temperature.
When two objects with different temperatures come in contact with one another, energy moves from the hotter (higher temperature) object to the cooler (lower temperature) object until both objects reach the same temperature.
The latitude of the location has an impact on the air temperature there. The location's elevation. separation from the ocean.
Thus, option B, C, D and E are correct.
To learn more about the temperature, follow the link;
https://brainly.com/question/11464844
#SPJ6
Determine the molar mass of water (H2O) using the periodic table. Express your answer to the correct number of significant figures. The molar mass of water is grams/mole.
Answer:
18.015
Explanation:
That other guy is on something, their answer didn't relate to the question at all. Anyways.. Jesus loves YOU!
Here is the answer in picture form
For+the+reaction+H2+++I2+-+2HI+the+equilibrium+constant,+kc+is+49+at+a+fixed+temperature.+Two+mole+of+hydrogen+and+two+moles+of+iodine+are+allowed+to+reach+equilibrium+at+this+temperature.+What+is+the+concentration+of+hydrogen+iodide+at+equilibrium?
Answer : The initial concentration of HI and concentration of HI at equilibrium is, 0.27 M and 0.386 M respectively.
Solution : Given,
Initial concentration of H_2 and I_2 = 0.11 M
Concentration of H_2 and I_2 at equilibrium = 0.052 M
Let the initial concentration of HI be, C
The given equilibrium reaction is,
H_2(g)+I_2(g)\rightleftharpoons 2HI(g)
Initially 0.11 0.11 C
At equilibrium (0.11-x) (0.11-x) (C+2x)
As we are given that:
Concentration of H_2 and I_2 at equilibrium = 0.052 M = (0.11-x)
The expression of K_c will be,
K_c=\frac{[HI]^2}{[H_2][I_2]}
54.3=\frac{(C+2(0.058))^2}{(0.052)\times (0.052)}
By solving the terms, we get:
C = 0.27 M
Thus, initial concentration of HI = C = 0.27 M
Thus, the concentration of HI at equilibrium = (C+2x) = 0.27 + 2(0.058) = 0.386 M
The law of conservation of energy states that energy cannot be created or . However, energy can be from one substance to another.
Answer:
destroyed.
transferred.
Explanation:
hehe
Answer:
Your answer would be destroyed and Transferred.
Explanation:
The reason why is because energy is never created or destroyed because it is just transferred to different forms of energy. Suich as a ball at the top of a hill. It's not moving, so it has potential energy, (potential energy is energy that is stored) and let's say that some wind comes through and gives that ball a push, so now the ball is moving and is going downhill. now the ball has kinetic energy because it was transferred to a moving energy from a stored energy.
Write the difference between the reaction of Calcium and Aluminium with water.
Answer:
Both gives hydroxides, but
Calcium reacts with water to give calcium hydroxide Ca(OH)2. this product is slightly soluble in water.
Aluminium is less reactive than Ca, so it reacts with only steam, to give aluminium hydroxide Al(OH)3. This product is insoluble in water.
DNA is an example of a:
O A. Compound
B. Element
c. Mixture
D. Atom
Answer:
The answer is option A.
Compound
Hope this helps you
What reaction is depicted by the given equation: Au3+ + 3e− Au
A. oxidation B. reduction C. combustion D. replacement E. neutralization
Answer:
The answer is option B.
Reduction
Hope this helps you
Answer:
plato answer b
Explanation:
2. Se combinan 40 g de SO2 y 25 g de O2 determine el porcentaje en masa del exceso con respecto a su masa inicial. P.A. (S = 32; O = 16) SO2 + O2 SO3
Answer:
60%
Explanation:
En la reacción:
2SO₂ + O₂ → 2SO₃
Donde 2 moles de SO₂ reaccionan por mol de O₂.
El peso atómico del SO₂ es:
1S = 32g/molₓ1 = 32g/mol
2O = 16g/molₓ2 = 32g/mol
SO₂ = 32g/mol + 32g/mol = 64g/mol
Y el peso atómico de O₂ es:
2O = 16g/molₓ2 = 32g/mol
Las moles de SO₂ y O₂ son:
SO₂: 40g ₓ (1mol / 64g) = 0.625 moles
O₂: 25g ₓ (1mol / 32g) = 0.7813 moles
Para una completa reacción de SO₂ se necesitan:
0.625 moles SO₂ ₓ (1mol O₂ / 2 mol SO₂) = 0.3125 moles de O₂
Así, las moles en exceso de O₂ son:
0.7813 moles - 0.3125 moles = 0.4688 moles O₂
En gramos:
0.4688 moles O₂ ₓ (32g / mol) = 15g O₂ están en exeso.
El porcentaje en exceso es:
15g / 25g ₓ 100 =
60%What type of contamination do peroxides produce?
Answer:
The main hazard related to organic peroxides are their fire and explosion hazards. ... It is the double oxygen of the "peroxy" group that makes organic peroxides both useful and hazardous. The peroxy group is chemically unstable. It can easily decompose, giving off heat at a rate that increases as the temperature rises.
Explanation:
How many atoms are present in a Neon molecule? *
Answer:
Neon molecule does not exist.
Explanation:
Neon is denoted by Ne which is noble gas. According to the "Molecular Orbital Theory", only those molecules exist that have a positive bond order and molecules with no bond or negative bond order cannot exist.
Consider the chemical equations shown here.
P4(s) + 302(g) - P406(S) AH1 = -1,640.1 kJ
P4010(s) - P4(s) + 5O2(g) AH2 = 2,940.1 kJ
What is the overall enthalpy of reaction for the equation shown below?
Round the answer to the nearest whole number.
P406(S) + 2O2(g) → P4010(s)
DONE
Answer:
-1,300 kJ
Explanation:
P₄ + 3 O₂ ⇒ P₄O₆ ΔH = -1,640.1 kJ (EQ 1)
P₄O₁₀ ⇒ P₄ + 5 O₂ ΔH = 2,940.1 kJ (EQ 2)
These are the equations you are given. You need to make these equations into the equation below.
P₄O₆ + 2 O₂ ⇒ P₄O₁₀ (end equation)
Look at the product side of the end equation. You need to produce P₄O₁₀. In the EQ 2, P₄O₁₀ is on the reactant side. Flip the equation. Since you flipped the equation, the enthalpy will have the opposite sign.
P₄ + 5 O₂ ⇒ P₄O₁₀ ΔH = -2,940.1 kJ
On the reactant side of the end equation, you need P₄O₆ and 2 O₂. First, rearrange the equation so that P₄O₆ is on the right side. In EQ 1, P₄O₆ is on the product side. Flip the equation. Like the last one, the sign will change.
Now, cancel out all possible values. P₄ will cancel out since there is one on each side of the equation. Since there is 5 O₂ on one side and 3 O₂ on the other, subtract the two and put the remainder on the side of the larger value.
P₄ + 5 O₂ ⇒ P₄O₁₀ ΔH = -2,940.1 kJ
P₄O₆ ⇒ P₄ + 3 O₂ ΔH = 1,640.1 kJ
P₄O₆ + 2 O₂ ⇒ P₄O₁₀
This should be the resulting equation. Now, add the two enthalpies together to find the overall enthalpy.
-2,940.1 kJ + 1,640.1 kJ = -1,300 kJ
The overall enthalpy is -1,300 kJ.
-867.7Answer:
Explanation:
-867.7
Of the following, which can be used to identify an element present in a sample?
Answer:
idk but i tryed
Explanation:
The simplest way to use the periodic table to identify an element is by looking for the element’s name or elemental symbol. The periodic table can be used to identify an element by looking for the element’s atomic number. The atomic number of an element is the number of protons found within the atoms of that element.
Does anybody know how to do q4. Please show working out thanks.
Answer:
% purity of limestone = 96.53%
Explanation:
Question (4).
Weight of impure CaCO₃ = 25.9 g
Molecular weight of CaCO₃ = 40 + 12 + 3(16)
= 100 g per mole
We know at S.T.P. number of moles of CO₂ = 1 and volume = 22.4 liters
From the given reaction, 1 mole of CaCO₃ reacts with 1 mole or 22.4 liters of
CO₂.
∵ 22.4 liters of CO₂ was produced from CaCO3 = 100 g
∴ 1 liter of CO₂ will be produced by CaCO₃ = [tex]\frac{100}{22.4}[/tex]
∴ 5.6 liters of CO₂ will be produced by CaCO₃ = [tex]\frac{100\times 5.6}{22.4}[/tex]
= 25 g
Therefore, % purity of CaCO₃ = [tex]\frac{\text{Weight calculated}}{{\text{Weight given}}}\times 100[/tex]
= [tex]\frac{25}{25.9}\times 100[/tex]
= 96.53 %