Answer:
There must be added 500 cm3 of alcohol to bring the concentration to 80%.
Explanation:
Concentration
The concentration of a solution is a measure of the amount of solute that has been dissolved in a given amount of solution.
In the container, there are 2 liters (2000 cubic centimeters) of a solution, 75% of which is alcohol (solute) and 25% of water (solvent).
The original amount of alcohol is:
H = 2000*75% = 1500 cc
The original amount of water is:
W = 2000*25% = 500 cc
When we add x cc of pure alcohol, there are 1500+x cc of alcohol out of 2000+x cc of solution.
The new concentration is calculated as:
[tex]\displaystyle \frac{1500+x}{2000+x}[/tex]
And it's known this concentration is 80% (0.8), thus:
[tex]\displaystyle \frac{1500+x}{2000+x}=0.8[/tex]
Multiplying by 2000+x:
[tex]1500+x = 0.8(2000+x)[/tex]
Operating:
[tex]1500+x = 1600+0.8x[/tex]
Rearranging:
[tex]x-0.8x=1600-1500[/tex]
[tex]0.2x=100[/tex]
[tex]x=100/0.2[/tex]
x= 500
There must be added 500 cm3 of alcohol to bring the concentration to 80%
Rosa was looking for patterns to help predict the products of chemical reactions. She recorded three similar decomposition reactions in the table.
A 2-column table with 3 rows. The first column labeled reactants has entries 2 N a C l O subscript 3, 2 K C l O subscript 3, 2 L i C l O subscript 3. The second column labeled products has entries 2 N a C l + 3 O subscript 2, 3 O subscript 2 + 2 K C l, empty.
What products should she record in the last row of the table?
2LiCl + 3O2
3LiCl + 2O2
2LiO + 3Cl2
3LiO+ 2Cl2
Answer:
It's A
Explanation:
Because I know it is
The record in the last row should be 2LiCl + 3O2.
What is a chemical reaction equation?A chemical reaction equation has two parts;
The left hand side that contains the reactants.The right hand side that contains the products.The interaction between the atoms of the reactants lead to rearrangement hence products are formed.
For the reaction, the record in the last row should be 2LiCl + 3O2.
Learn more about chemical reaction:https://brainly.com/question/6876669
does anyone know the answer to this ?????
Answer:
as fuel is combusted,the rocket pushes the gas is backward and the gas is pushed the rocket forward
Explanation:
hope this helps :]
Which of these is an example of a longitudinal wave?
Answer:
D. Sound waves
Explanation:
The following options are missing:
A. radio wave
B. X-rays
C. Light waves
D. Sound waves
There are two kinds of waves: longitudinal and transverse.
In longitudinal waves, the vibrations are parallel to the direction of wave travel. Examples of longitudinal waves include: sound waves and ultrasound waves.
In transverse waves, the vibrations are at right angles to the direction of wave travel. All electromagnetic waves (e.g. light waves, microwaves, radio waves and X-rays) are transverse waves.
View the chart on the characteristics of electromagnetic and mechanical waves and answer the question.
Electromagnetic Waves Mechanical Waves
Transverse Waves Transverse, Longitudinal, and Surface Waves
Do not require a medium Require a medium
Begin with the movement of charged particles Begin when matter is disturbed
How is the transfer of energy different in electromagnetic waves compared to mechanical waves?
a
Electromagnetic waves requires a source of energy
b
Electromagnetic waves can transfer energy through a vacuum, or empty space
c
Electromagnetic waves create a vibrating electric field
d
Electromagnetic waves can change speed or direction
Answer:
a
Explanation:
Will give
Creep meters and laser-ranging devices measure horizontal fault movement.
Please select the best answer from the choices provided
T
F
Answer:
True
Explanation:
Answer:
True.
Explanation:
Hope this helps!!! <3
Why are bubbles round?
(A serious physics question)
Answer:
The Science of Round Bubbles
But once a bubble is sealed and removed from the wand, the tension in the bubble shrinks it to the smallest possible shape for the volume of air inside of it. That's a sphere, which is the familiar round shape we see when bubbles float through the air.
Explanation:
What is the density of 15 cm3 and 3 g?
Answer:
0.2
Explanation:
3/15
A bowling ball weighing 71.2 N is swinging like a pendulum at the end of a 3.8 m rope.
As the ball swings through its lowest point, its speed is measured at 4.2 m/s. What is
the magnitude and direction of the acceleration of the ball at this point?
A. 4.64 m/s, upward
B. 4.64 m/s, downward
C. 5.16 m/s, upward
D. 5.46 m/s, downward
Answer:
A
Explanation:
Do atomic bombs and nuclear reactors function in the same manner?
Answer:
No, they do not function in the same manner.
Explanation:
I actually don't know why.
7. A ship can carry heavier load in salty water than that in fresh water, why?
Because of the buoyancy of the salt particles
A cannon is fired with an initial horizontal velocity of 20 m/s and initial vertical velocity of 25 m/s. After 3s in the air, the canon hits its target. How far away was the canon from its Target?
Answer:
140.16m
Explanation:
To get the distance the cannon is away from its target, we will apply the equation of motion;
S = ut + 1/2gt²
u is the resultant initial velocity
g is the acceleration due to gravity
t is the time taken.
Given
g = 9.8m/s²
t = 3s
u = √20²+25²
u = √400+625
u = √1025
u = 32.02m/s
Substitute the values into the formula and get the distance S;
S = 32.02(3)+ 1/2(9.8)3²
S = 96.06+44.1
S = 140.16m
Hence the cannon was 140.16m away from its target
PLEASE HELP!!!!! thx
Answer:
I thick it's ccc not for sure
20 points HELP‼️ Which is more important in developing who
you are-environment or genetics? Explain why you believe this.
Answer:
Environment
Explanation:
Your Environment, More Than Genetics, Determines Your Immune Health. When it comes to immunity, the environment you grow up in, or how you were 'nurtured' , is more important than nature, a new study suggests. Particularly as you get older.
Where would you find the photosphere
PLS HELP ITS WORTH SO MANY POINTS AHH
LONGITUDINAL
SURFACE
TRANSVERSE
HEAT
Answer:
C. transverse
A 5 kg ball rolling at 1.0 m/s hits a 15 kg ball at rest. The balls stick together after the collision What is the
velocity of the two balls after the collision?
Answer:
0.25m/s
Explanation:
Given parameters
m₁ = 5kg
v₁ = 1.0m/s
m₂ = 15kg
v₂ = 0m/s
Unknown:
velocity after collision = ?
Solution:
Momentum before collision and after collision will be the same. For inelastic collision;
m₁v₁ + m₂v₂ = v(m₁ + m₂)
Insert parameters and solve for v;
5 x 1 + 15 x 0 = v (5 + 15 )
5 = 20v
v = [tex]\frac{5}{20}[/tex] = 0.25m/s
Due to the friction between a tire and the road surface, the temperature of the air inside a tire increases as one drives. If the tire pressure is 37 psi when the car is in the driveway at 25° C, What is the pressure of the tire when the temperature increases to 50° C?
Answer:
40.10 atm .
Explanation:
Here volume of tire is assumed to be nearly constant .
Modified gas law ,
P₁ / T₁ = P₂ / T₂
37 / ( 273 + 25 ) = P₂ / ( 273 + 50)
37 / 298 = P₂ / 323
P₂ = 37 x 323 / 298
= 40.10 atm .
A juggler throws a beanbag into the air with a speed of 1.0 m/s.
How long does it take for the beanbag to reach its maximum height?
An object is projected straight upward with an initial speed of 25.0 m/s. What's the maximum height obtained by the object ?
Answer:
The maximum height obtained by the object is approximately 31.855 m
Explanation:
The vertical velocity of the object = 25.0 m/s
The height reached by the object, is given by the following formula;
v² = u² - 2 × g × h
Where;
u = The initial velocity of the object = 25.0 m/s
v = The final speed of the object = 0 m/s at maximum height
h = The maximum height obtained by the object
g = The acceleration due to gravity = 9.81 m/s²
Substituting the values, gives;
0² = (25.0 m/s)² - 2 × 9.81 m/s² × h
2 × 9.81 m/s² × h = (25.0 m/s)²
h = (25.0 m/s)²/(2 × 9.81 m/s²) ≈ 31.855 m
The maximum height obtained by the object, h ≈ 31.855 m.
PLS HELP DUE AT 10 PM
Each of the diagrams below represents one of the three states of matter.
Identify the state of matter that each diagram represents, and explain how you know. Then, describe an
example of each state of matter from everyday life.
solid, liquid,gasses
PLS HELP THIS IS DUE IN TWO HOURS
Answer:
C
Explanation:
Un montañero de 65kg de masa ha ascendido a la cima del Everest, la montaña más alta del mundo de 8848m de altura sobre el nivel del mar. Calcula el trabajo que ha realizado para subir los últimos 500m
Answer:
El trabajo realizado para subir los últimos 500 metros es 318727,5 joules.
Explanation:
Por la definición de trabajo sabemos que el montañero debió contrarrestar trabajo causado por la gravedad terrestre. Si asumimos que el cambio de la altura es muy pequeño en comparación con el radio del planeta (6371 kilómetros vs. 0,5 kilómetros), entonces podemos considerar que la aceleración gravitacional es constante y la ecuación de trabajo ([tex]\Delta W[/tex]), medido en joules, que reducida a:
[tex]\Delta W = m\cdot g\cdot \Delta z[/tex] (1)
Donde:
[tex]m[/tex] - Masa del montañero, medido en kilogramos.
[tex]g[/tex] - Aceleración gravitacional, medida en metros por segundo al cuadrado.
[tex]\Delta z[/tex] - Distancia vertical de ascenso del montañero, medida en metros.
Si tenemos que [tex]m = 65\,kg[/tex], [tex]g = 9,807\,\frac{m}{s^{2}}[/tex] y [tex]\Delta z = 500\,m[/tex], entonces el trabajo realizado por el montañero para subir es:
[tex]\Delta W = (65\,kg)\cdot \left(9,807\,\frac{m}{s^{2}} \right)\cdot (500\,m)[/tex]
[tex]\Delta W = 318727,5\,J[/tex]
El trabajo realizado para subir los últimos 500 metros es 318727,5 joules.
draw a distance time graph for uniformly accelerated motion when object is an rest?
Answer: Distance-time graph is the plot of distance travelled by a body against time. Below is an example of a distance-time graph, if it is a straight horizontal line than the body is stationary, its speed is zero, if the line is diagonal than its moving with a constant speed and if it is anything other than a straight line then the speed is varying. Distance-Time Graph for Uniform Motion Let us now consider a distance-time graph in which the body is moving with uniform motion. A body is said to be in uniform motion when the body covers the equal distance in equal time intervals. Let’s consider a time interval of 1 second, If a body covers 10 meters in the first 1-second then it should cover 10 meters in every second from there on, this will indicate that the body is in uniform motion.
Explanation: I hoped that helped!!
Cody’s car accelerates from 0m/s to 65 m/s northward in 25 seconds. What is the acceleration of the car?
Answer:
v=v(initial)+at
45=0+15a
a= 3m/sec²
Explanation:
edge 2020
Motion of a potter's wheel is an example of
motion
Answer:
bus , running boy etc
Explanation:
moving body is called motion .
e.g. running boy , bus, birds flying etc
In 1900, a German physicist discovered an equation that matched experimental data about the emission of light by a hot surface. *
a. Max Planck
b. Sir Isaac Newton
c. James Clerk Maxwell
d. Christian Huygens
How do I graph distance ,speed ,velocity, and acceleration?
Answer:
distance is how much space is between, speed is how fast they are going, velocity is money and acceleration is going
Explanation:
Un vagón de carga de 5000-kg se mueve a 2m/s e impacta a un vagón de 10000-kg que se encuentra en reposo. Después de la colisión inelástica a que rapidez se mueven.
Answer:
0.67 m/s
Explanation:
Mass of car 1, m₁ = 5000 kg
Mass of car 2, m₂ = 10,000 kg
Initial speed of car 1, u₁ = 2 m/s
Final speed of car 2, u₂ = 0 (at rest)
We need to find the final velocity of both cars when inelastic collision occurs. The momentum will remain conserved in case of inelastic collision. Using the conservation of momentum. Let V is the final speed.
[tex]m_1u_1+m_2u_2=(m_1+m_2)V\\\\\V=\dfrac{m_1u_1+m_2u_2}{(m_1+m_2)}\\\\V=\dfrac{m_1u_1}{(m_1+m_2)}\\\\V=\dfrac{5000\times 2}{(5000+10000)}\\\\V=0.67\ m/s[/tex]
So, after the inelastic collision, they will move with a speed of 0.67 m/s.
is it true or false that chemical change like baking a cake normally has a color change?