Answer:
7.36
Explanation:
my teacher said that was the right answer
Calculate the mass percentage of each element in aluminum oxide.
Answer:
So, Percentage Composition of Aluminium = 2778×100%=34.62% (approx.) Percentage Composition of Oxygen = 3×1678×100%=61.54% (approx.)
If there is direct variation and y=75 when x=25, find x when y=48.
A. x=16
B. x=10
C. x=12
D. x=14
If there is direct variation and y=75 when x=25,when y=48 X = 16. Therefore, option A is correct.
What is direct variation ?link between two variables that can be described mathematically by an equation where one variable equals a constant multiplied by the other. For instance, the constant of variation is k = = 3 if y varies straight as x and y = 6 when x = 2. Consequently, y = 3x is the equation that describes this direct variation.
When x is not equal to zero, an equation of the form y = kx describes the linear function known as direct variation. When x is not equal to zero and k is a nonzero real number constant, the equation of the form xy = k describes the nonlinear function known as inverse variation.
x = ky
where k is constant
25 = k × 75
25 / 75 = k
k = 1 / 3
now when y = 48 then substitute the values
x = ky
x = 1 ÷ 3 × 48
x = 16
Thus, option A is correct.
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pa help po science po
Answer:
1. molecule, cell, tissue, organ, organ system, organism, population, community, ecosystem, biosphere
2. A
3. D
4. C
5. C
6. C
7. C
8. B
9. Sorry I don't know :(
10. B
11. A
12. C
13. Sorry :((
14. C
15. a
16. d
Sorry I don't know the rest.. I hope this helps though!!
15. Explain the advantage of using spectral analysis in the identification of an elemental
species over that of using FLAME TESTS?
Answer:
to identify the element by using flame tests
Serena mixed two samples together: a gray solid that smells like flowers and a gray solid that smells like bleach. She analyzed the results and found two ending substances. One of the ending substances was a white solid. This ending substance is made up of the repeating group of atoms shown above. Which of the diagrams to the left shows the repeating groups of atoms that make up the samples Serena mixed together?
The diagrams that shows the repeating groups of atoms that make up the samples which were mixed together is option D.
A chemical reaction is said to have occurred when there a rearrangement of atoms in a substance. This rearrangement of atoms in the substance leads to the formation of new substances.
In this case, we must note that the combination of reactants to be chosen must posses the atoms shown as part of the one of the end substance. The only option that satisfies this requirement is option D.
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Answer:D
Explanation:DDDDD
Brainliest for best answer
b is answer
Explanation:
please follow me
Answer:
B is the answer
Explanation:
A is incorrect as there is 2 O2 on the RHS while there is only 1 O2 on one side
B is correct as it is going through a process called combustion and I don't feel like explaining it is too long T^T
C is incorrect as the 3 results in multiply N (3 Nitrogen) while there is only one N2
D is definitely incorrect -.-
Hope this helps
(P.S. I lost a lot of my brain cells x-x)
does the following atomic model of a chemical reaction correctly demonstrate the law conservation of matter why or why not plz help
Answer:
ZH² + O² = ZH²O I think this may help you I don't really know how to explain
Which list correctly compares how adding energy affects a substance during a phase change and not during a phase change?(1 point)
during a phase change: particles overcome forces of attraction and temperature stays the same
not during a phase change: particles become closer together
during a phase change: particles overcome forces of attraction and temperature stays the same
not during a phase change: temperature rises
during a phase change: particles overcome forces of attraction and temperature rises
not during a phase change: particles become closer together
during a phase change: particles overcome forces of attraction and temperature rises
not during a phase change: temperature rises
Which action happens at the microscopic scale as the temperature of a substance decreases and it eventually freezes?(1 point)
Particle motion decreases, and electrostatic forces pull particles closer together.
Particle motion increases, and the particles overcome electrostatic forces.
Particle motion decreases, and the particles overcome electrostatic forces.
Particle motion increases, and electrostatic forces pull particles closer together.
Which statement describes how a macroscopic property of gases provides information about microscopic gas particles?(1 point)
Gases fill their container, showing that gas particles are strongly attracted through electrostatic forces.
Gases have a fixed volume, showing that gas particles are strongly attracted through electrostatic forces.
Gases fill their container, showing that gas particles are not tied together and can move far apart.
Gases have a fixed volume, showing that gas particles are not tied together and can move far apart.
Answer:
1) during a phase change: particles overcome forces of attraction and temperature stays the same not during a phase change: temperature rises 2)Particle motion decreases, and electrostatic forces pull particles closer together.
3) Gases fill their container, showing that gas particles are not tied together and can move far apart.
Explanation:
natural gas has been stored in an expandable tank that keeps a constant pressure as gas is added or removed. the tank has a volume of 4.50x 104 ft 3 when it contains 77.4 million mole natural gas at - 5 °c. what is the new volume of the tank if consumers use up 5.3 million mole and temperature increase to 7 °c?
Answer:
5-3. Ice water 0 "C. A steel tank contains carbon dioxide at 27 "C and a pressure of 12.0 atm.
Explanation:
which type of element pairs can form ionic bonds
Answer:
Between metal and nonmetal ion's
Explanation:
for example, sodium (Na),a metal and a chloride (Ci
what is oxidation number on Ni in the next compound
K2[NiBr6] ???
Explanation:
The oxidation number of Ni is +4
The ion of aluminum is
Al+
Al2-
Al2+
Al3+
Al3-
Answer:
A13+
Explanation:
I took a test that had this question.
The effect of a catalyst is to: change the stoichiometry of the reaction. lower the activation energy of a reaction whereby making it easier for the reactants to get over the energy hump. change the position of the equilibrium. increase the number of collisions between reactants. increase the temperature of the reactants whereby more products are forme
The effect of a catalyst is
Option B(lower the activation energy of a reaction whereby making it easier for the reactants to get over the energy hump)What is a catalystA catalyst allows an alternative reaction pathway that leaves activation energy than the uncatalysed reaction. This does not change the frequency of collision.
Frequency of collisionFrequency of collision depend upon concentration of reactant temperatures
Catalyst on activation energyHence, catalyst lowers the activation energy of reaction thereby making it easier for the reactant to get over the energy hump.
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How many atoms of copper in 3. 11 g of copper
Hope you could get an idea from here.
Doubt clarification - use comment section.
Why was the war in Peru difficult?
Answer:
in contrast, peru and Bolivia entered the war hindered by numerous domestic fractures and by an economic and insititutional backwardness that nearly prevented the two countries from fighting the war at all
Please help help helpppppppp
Write the symbol for every chemical element that has atomic number less than 13 and atomic mass greater than 17.2 u.
Heart, 5 stars, Brainiest, and 40 coins if right! Answer needed ASAP
Which statement describes what happens when Bret runs up a flight of stairs?
A. His kinetic energy is destroyed.
B. His potential energy decreases.
C. His kinetic energy is converted into potential energy.
D. His potential energy is converted into kinetic energy.
Answer:
His kinetic energy is converted into potential energy.
Explanation:
How do many types of cells, like bacteria, reproduce?
Answer:
cells like bacteria are bisexual so they split and their offspring is 100 percent like the parent and this process happens over and over
Explanation:
How are the sensory clues from watching a fire different from the sensory clues from watching a firefly?
Answer:
sensory experience of a chemical reaction called combustion. In a way, fire is like the leaves changing color in fall, the smell of fruit as it ripens, or a firefly's blinking light. All of these are sensory clues that a chemical reaction is taking place
Explanation:
Sensory encounter with the combustion chemical process. Fire can be compared to the fall foliage's shifting hues, the aroma of ripe fruit, or the blinking light of fireflies. These are all sensory indicators that a chemical reaction is occurring.
What is combustion?Combustion is defined as a chemical interaction between different compounds, usually involving oxygen, that produces heat and light in the form of flames. Hydrocarbons and oxygen are the only reactants in a combustion reaction. The fuel is a hydrocarbon, and oxygen is required for burning.
It stimulates several of our senses at once, producing the vivid experience we anticipate from a tangible object. By using fuel, heat, and oxygen during combustion, that sensory experience is produced.
Thus, sensory encounter with the combustion chemical process. Fire can be compared to the fall foliage's shifting hues, the aroma of ripe fruit, or the blinking light of fireflies. These are all sensory indicators that a chemical reaction is occurring.
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what is the wavelength of a photon emitted when an electron jumps from n=2 to n= 1 energy level of a single ionized helium atom ?
Answer:
I hope it help you the wavelength is 1.9130E-28
what is the mass in g of 7.009 x 10^21 molecules of Pl3?
A mixture of 0.384 M H2O, 0.384 M Cl2O, and 0.652 M HClO are placed in a vessel at 25 oC. Calculate the equilibrium concentration (in molarity) of HClO at the same temperature.
Equilibrium concentration of HOCl at 25°C is 0.140 M
The equation of the reaction at equilibrium is given below:
H₂O (g) + Cl₂O (g) ⇄ 2 HOCl (g)
Equilibrium constant, Kc = 0.0900 at 25°C
An ICE chart for the reaction is set up below
H₂O (g) + Cl₂O (g) ⇄ 2 HOCl (g)
I 0.384 0.384 0.652
C -x -x + 2x
E 0.384 - x 0.384 - x 0.652 + 2x
The equation of the equilibrium constant is given as;
Kc = [tex]\frac{[HOCl]^2}{[H_{2}O][Cl_{2}O]}[/tex]
substituting the values into the equation:
Kc = [tex]\frac{(0.652 + 2x)^2}{( 0.384 - x)( 0.384 - x)}[/tex] = 0.0900
4x² + 2.608x + 0.425 = 0.0900 (0.147 - 0.768x + x²)
4x² - 0.09x² + 2.677x - 0.069x + 0.425 - 0.013 = 0
3.910x² + 2.677x + 0.412 = 0
Solving using the quadratic formula:
a = 3.910, b = 2.677, c = 0.412
x = [tex]\frac{-2.677\±\sqrt{2.677^2 - 4*3.910*0.412}}{2*3.910}[/tex]
x = -0.256 or -0.431
The negative sign indicates that equilibrium is to the left of the reaction
Since x cannot be greater than 0.384, x = -0.256.
Equilibrium concentration of HOCl = 0.652 + 2(-0.256)
Equilibrium concentration of HOCl at 25°C is 0.140 M
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define conjugate Base and conjugate acid
Explanation:
conjugated base is substance formed when an acid loses
a hydrogen ion.
conjugated acid is a type of acid that is formed when a base accepts a proton in solution
Need asap thank you
Answer:
c.boron-11
Explanation:
The atomic mass of boron is 10.81 u.
And 10.81 u is a lot closer to 11u than it is to 10u, so there must be more of boron-11.
To convince you fully, we can also do a simple calculation to find the exact proportion of boron-11 using the following formula:
(10u)(x)+(11u)(1−x)100%=10.81u
Where u is the unit for atomic mass and x is the proportion of boron-10 out of the total boron abundance which is 100%.
Solving for x we get:
11u−ux=10.81u
0.19u=ux
x=0.19
1−x=0.81
And thus the abundance of boron-11 is roughly 81%.
Why must labs that use mercury thermometers calculate Kelvin ?
Answer:
because those are the only thermometers that are truly accurate for kelvins
Explanation:
The Kelvin temperature in thermometers is used by scientists because it provides a temperature where zero indicates the complete absence of thermal energy.
What is the Kelvin scale?All thermometers have a scale on them that we use to find the temperature, known as a temperature scale. Kelvin proposed that the temperature interval from the ice point to the steam point be defined as 100° containing earlier centigrade scales.
Lord Kelvin had given an absolute temperature scale based on the Carnot cycle. The zero point is 273.15 on Kelvin’s scale below that of the Celsius scale.
On the kelvin scale, Each division is called a Kelvin (K) and is equal to a degree on the Celsius scale. On the Celsius scale, zero degrees is the freezing point of water while on the Kelvin scale the zero point is at absolute zero temperature.
Therefore, 0 K is equal to - 273.15°C, and 0°C is equal to 273.15 kelvins. A mathematical expression that gives the relation between the Celsius and Kelvin scales:
Temperature (K) = Temperature (°C) + 273
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In general, people of __ heritage will be the last to get
white hair.
Answer:
African?
Explanation:
How how how how how
Hello Americans greetings from the Philippines
Answer:
good day philipines
Explanation:
Answer:
hello
Explanation:
explain why soaps are soluble in water but fatty acids are not?
Answer:
Because of the two different parts of the molecule, a soap molecule is soluble in water and at the same time can dissolve fats. The fats are attracted to the non-polar tail part of the soap while the polar head makes the whole complex.
Explanation:
hope it helps
what is the correct sequence of stages in cellular respiration
Answer:
Explanation:
Glycolysis
Pyruvic acid oxidation
Curbs cycle or citric acid cycle.
Respiratory chain.
Have a great night!