4. How does a molecule differ from an atom? (4 points)
1. Of the following, the one that is not an example of a suspension is
a. Milk
b. Milk of magnesia
c. Sand in water
d. Sugar in water
2. The word used to represent a chemical reaction is a/an
a. Atom
b. Formula
c. Equation
d. Symbol
3. When two similarly charged objects are brought close together, they
a. Repel each other
b. Have no effect on each other
c. Stick to each other
d. Attract each other
4. An element common to all acids is
a. Chlorine
b. Hydrogen
c. Nitrogen
d. Oxygen
5. Atoms of the same element that differ slightly in mass are called
a. Ions
b. Isotopes
c. Neutrons
d. Positrons
6. In general, salts
a. Contain hydroxide ions
b. Contain hydrogen ions
c. Are ionic compounds
d. Turn blue litmus red.
7. A dye used to test the acidity of a substance is
a. Litmus
b. Magnesium sulfate
c. Sodium chloride
d. Sodium hydroxide
8. The central portion of an atom is called the
a. Electron
b. Nucleus
c. Ring
d. Shell
9. Sugar is poured into a glass of water and stirred. In this example the sugar is the
a. Solution
b. Solvent
c. Solute
d. Alcohol
10. Which of the following is characterized by a sour taste?
a. Bases
b. Acids
c. Salts
d. Compounds
11. Which of the following is characterized by a bitter taste and turn lithmus blue?
a. Bases
b. Acids
c. Compounds
d. Elements
12. The force of gravity on an object is called
a. Density
b. Mass
c. Volume
d. Weight
13. The liquid referred to as the “universal solvent” is
a. Alcohol.
b. Benzene.
c. Oil.
d. Water.
14. A statement that proposes a cause-and-effect relationship between two variables is called:
a. Conclusion.
b. Fair test.
c. Hypothesis.
d. Theory
15. Any substance that has mass and occupies space is called
a. A gas
b. A liquid
c. Matter
d. A solid
16. When the numbers of electrons and protons in a sample of matter are equal, the matter is
a. Insulated.
b. Negatively charged.
c. Neutral.
d. Positively charged.
17. Which of the following is most important when judging the quality of a scientific theory?
a. The quality and reliability of data that support the theory
b. The amount of detail provided in the theory
c. How recently the theory has been published
d. The respectability of the scientists setting forth the theory
18. Substances that cannot be decomposed to any simpler substances are called
a. Compounds.
b. Elements.
c. Mixtures.
d. None of the above.
19. When the air in a bell jar containing a ringing bell is removed, the sound decreases because
a. The removal of the air prevents electric current from flowing
b. Sound cannot travel through the air
c. Sound cannot travel through glass
d. Sound cannot travel in a vacuum
20. An element common to all acids is
a. Chlorine.
b. Oxygen.
c. Nitrogen.
d. Hydrogen.
21. The amount of matter in an object is best expressed by its
a. Density
b. Mass
c. Volume
d. Weight
22. A substance that increases the rate of a reaction is a
a. Liquid
b. Gas
c. Catalyst
d. Solid
Answer: 1. C
Explanation: 2. C
Ax = 44.4 m and Ay = 25.1 m Find the direction of the vector.
Answer: 29.5 degree
Explanation: Given that
Ax = 44.4 m and Ay = 25.1 m
The direction of the vector will be
Tan Ø = Ay/Ax
Substitute Ay and Ax into the formula
Tan Ø = 25.1/44.4
Tan Ø = 0.5653
Ø = tan^-1(0.5653153)
Ø = 29.48 degree
Ø = 29.5 degree approximately.
Therefore, the direction of the vector is 29.4 degrees approximately.
Frames of Reference Practice Solutions
A girl is on a train that is headed East at 100 miles per hour. The girl is walking at 5 miles per hour
toward the back of the train.
1.
What is the speed and direction of the train if the girls is the frame of reference?
Answer:
5 mph East.
Explanation:
If the girl is the frame of reference, we need to check the train's relative movement to the girl.
If the girl was not moving inside the train, the speed of the train would be zero, because the train and the girl would be moving together with the same speed and direction.
If the girl is moving 5 mph toward the back of the train, the movement of the train should be calculated considering the girl is fixed (not moving).
So the direction of the train movement would be the inverse of the girls movement (the girl is going West), then the speed and direction of the train is 5 mph and East.
which type of circuit is shown?
A. closed series circuit
B. closed parallel circuit
C. open parallel circuit
D. open series circuit
Answer:
I think it's D. open series circuit .
Explanation:
hope it helps you!
A wave is traveling from one medium to another.If the wave is partially transmitted an partially reflected from the boundary,what will happen to the amplitude of the reflected wave?
Answer: the answer is C
Explanation:
What is the proper function of a linkage? *
1 point
a) transferring energy
b) transferring speed
c) transferring money
d) transferring weight
asap plz, for science loverz
brainliest for the best answer!
Answer:
a) transferring energy
Explanation:
A linkage is an assembly of parts connected together to control forces and movement. The connections between links are called joints and are used for ensuring movement, pure rotation or sliding.
Linkages provides a means in which kinetic energy is being transferred in different directions within a system. This Linkages can be used to Change force direction, size of force applied or the motion created by the force.
Which diagram is the best model for a solid ?
What force is required to give an object with mass 2000 kg an acceleration of
3.5 m/s2?
A. 571 N
B. 7000N
C. 10,500 N
D. 2535 N
Answer:
B
Explanation:
7,000N because the formula for finding force is F=MA (2000x3.5)N=7000N
How many suns do you think are in our galaxy? Explain your answer PLS HELP ASP BEST GETS BRAINLIEST
Answer: There is only one Sun in the galaxy … that is the thing that rises in the morning and sets at night. However, there is a use of “sun” to signify any old star … nobody knows exactly there might be trillions out there
Explanation:
If you drew magnetic field lines for this bar magnet, which statement would be true?
Arrows point away from south and toward north.
Arrows point toward both north and south.
Arrows point away from north and toward south.
Arrows point away from both north and south.
Answer:
the arrows would point away from the north and towards the south.
Explanation:
magnetic field lines form loops around the magnet and they start at the north pole and end at the north pole, meaning that the arrows on a diagram would point away from the north and towards south.
*PLS READ: so sorry I made a mistake in my answer, the loops formed start at the north and END AT THE SOUTH POLE!! I'm so sorry :(
Answer:
The answer is C.) Arrows point away from Norht and towards South.
Explanation:
I took the K12 quiz. The picture is linked at the bottom of my answer. Hope you have an awesome day! Good luck!
What does Ohm’s law state?
A. Current equal voltage time resistance
B. Voltage equals resistance divided by current
C. Voltage equals current divided by resistance
D. Voltage equals current time resistance
Answer:
The answer is D
Explanation:
A model of an atom is useful when it
Select one:
O a. is shown only as the planetary model
b. shows exactly what an atom looks like
c. helps to visualize processes that cannot be seen with our eyes
d. magnifies what the eye can't see
Two vectors which do not lie along the same line represent what kind of
motion?
A. Resultant motion
B. Scalar motion
C. One-dimensional motion
D. Two-dimensional motion
Why is it a good idea to explore the health and fitness field in terms of career
options?
O A. There are career opportunities that require a variety of skills and
talents.
O B. It's a growing field.
O c. Many options in this field allow you to help other people through
your job.
D. All of the above.
Answer: I think the answer is option D.
If you divide a speed in miles per minute by 60, you get the same speed
expressed in miles per
Answer here
How does the velocity change with time in uniform rectilinear motion of an object?
A car accelerates uniformly from 0 km/hr to 60 km/hr in 4.5 seconds. Which one of the following choices best represents the acceleration of the car?
(A) 13.3 m/s2
(B) 9.8 m/s2
(C) 4.8 m/s2
(D) 3.7 m/s2
(E) 0.37 m/s2
please show work
Answer:
The acceleration of the car is [tex]3.7\ m/s^2[/tex].
Explanation:
It is given that,
Initial speed of the car, u = 0
Final speed of the car, v = 60 km/h = 16.66 m/s
Time, t = 4.5 s
We need to find the acceleration of the car. It is equal to the change in velocity divided by time taken. It can be given by :
[tex]a=\dfrac{v-u}{t}\\\\a=\dfrac{16.66-0}{4.5}\\\\a=3.7\ m/s^2[/tex]
So, the acceleration of the car is [tex]3.7\ m/s^2[/tex]. Hence, this is the required solution.
_______ force can be thought of as either a push or a pull, as long as it
makes the object move in a circular path.
Answer: Centripetal
Explanation: The centripetal force refers to the acting on a body moving in a circular path. This force acts in the direction of the center of rotation. The centripetal force is given by :
F = mv^2 / r
Where m = mass of th body
v. = Velocity
r = radius of the circular path.
For an object to move in a circular path, the force required is called the centripetal force. It is measured in Kgms^-2. It is directly proportional to the product of the Mass and square of it Velocity and varies inversely to the Radius of its path.
Click on the boxes below to indicate the number of electrons or protons in each labeled position for a zinc atom (z=30, a=65). Please carefully note the specific information requested for the nucleus by the letter designation.
Answer:
A 35
B 2
C 8
D 18
E 2
Explanation:
The number of electrons in the positions of the Zn atom, A, B, C, D and E are 30, 2, 8, 18 and 2 respectively.
What is meant by electronic configuration ?The arrangement of electrons within the orbitals of an atom is known as its electronic configuration.
Here,
The atomic number, which is equal to the number of protons in every neutral atom, is made up of a constant number of electrons in each neutral atom.
The atomic number of an atom is represented by the letter Z.
The mass number of an atom is the sum of the number of protons and neutrons, which are together known as the nucleons, within the nucleus. It is represented by the letter A.
The atomic number of Zinc is given,
Z = 30
From the figure, the electronic configuration can be represented as,
A = 30
which is the total number of electrons in Zn atom.
B = 2
which is the innermost orbital.
C = 8
D = 18
E = 2
Hence,
The number of electrons in the positions of the Zn atom, A, B, C, D and E are 30, 2, 8, 18 and 2 respectively.
To learn more about electronic configuration, click:
https://brainly.com/question/29757010
#SPJ3
It takes 50 N to move a desk 0.4 m high. What is the work done? W=F*d *
a) 20 J
b) 125 J
c) 0.008 J
d) 100J
brainliest for the best answer, asap plz
for science lovers
Answer:
A) 20J
Explanation:
Work = Force x Distance
Force = 50N
Distance = 0.4M
Work = 50 x 0.4 = 20J
A plane increases its speed from 450 km/hr to 750 km/hr in 0.30 hour. What is its acceleration?
Answer:
The acceleration is found as:
a = 1000 km/h²
Explanation:
Initial speed of the plane = 450 km/h
Final speed of the plane = 750 km/h
Time taken = 0.3 h
Acceleration can be defined as the change of speed of the object divided by the time taken to bring that change
Acceleration is given as:
[tex]a=\frac{v_f-v_i}{t}[/tex]
where v(f) = 750 km/h , v(i) = 450 km/h , t = 0.3 h
Substitute the values in the equation of acceleration
[tex]a= \frac{750-450}{0.3}\\a=\frac{300}{0.3}\\a=1000 km/h^2[/tex]
This is the found result
A pot of water is boiled on a stove. Which of the following definitions of the system enables the most straightforward thermodynamic analysis of the process
A. The system is the pot and water.
B. The system is the stove, pot, and water.
C. The system is the building containing the stove.
D. The system is the entire Universe.
Answer:
A. The system is the pot and water.
Explanation:
Thermodynamics is an aspect in science which deals with the applications of heat energy. The useful applications of heat energy to perform work.
In the given question, the pot and water is the system which both absorbs heat energy from the stove. Thus, the system is a closed system since it shares heat energy with its surroundings.
The surrounding of the system extends from the boundary of the pot to the universe.
If earth had two moons, how might this affect the way we see eclipses here on earth?
Do you think a population besides the moon jellies’ consumer population (sea turtles) and resource population (zooplankton) could have caused the moon jelly population to increase in size?
Answer:
I didn't quite understand your question, but the moon jelly population will increase if there are either more zooplankton or less sea turtles.
More zooplankton means more food => higher population
Less sea turtles means that the moon jelly will be lest often consumed => higher population
Answer: Yes because the Orca will start to eat the moon jellies
Explanation: When the Sea Turtles start to get very low on population the Moon jellies are next in line also the sea turtles eat the moon jellies and since they eat the moon jellies the sea turtle has a bit of that taste in them so they will taste alike to the sea turtles.
The acceleration due to gravity on the Moon is less than the acceleration due to gravity on the Earth. Which of the following is true about the mass and weight of an astronaut on the Moon's surface, compared to Earth?
(A) Mass is less, weight is the same.
(B) Mass is the same, weight is less.
(C) Both mass and weight are less.
(D) Both mass and weight are the same.
(E) Mass is more, weight is less.
Answer:
(B) Mass is the same, weight is less.
Explanation:
Just took test
how has E=MC2 helped us with our understanding of how stars like our Sun create energy?
Answer: please find the answer in the explanation
Explanation:
E = MC^2
Where
E = energy
M = mass
C = speed of light.
This equation is an eyes opener about the relationship between matter and energy. Its explanation about how matter can become energy and how energy can also give information about matter.
It helps us to understand the fusion and fission of both sun and star particles which eventually give us the result of the magnitude of energy they emit or radiate.
What is the velocity of the objects position vs time graph
Answer: In a position-time graph, the velocity of the moving object is represented by the slope, or steepness, of the graph line. If the graph line is horizontal, like the line after time = 5 seconds in Graph 2 in the Figure below, then the slope is zero and so is the velocity. The position of the object is not changing
The mean diameter of the Earth is 12.76 x 103 km. What is the surface area of the Earth in m2 ?
(A) 4.01 x 107
(B) 5.12 x 1014
(C) 1.09 x 1021
(D) 1.68 x 109
(E) 2.05 x 1015
Answer:
The Answer is B
Explanation:
Hope this Helps :D
How do you represent an object in a free body diagram?
A)An object is represented in a free-body diagram by an arrow and tail.
B)An object is represented in a free-body diagram by a box with a dot in
the middle, indicating its center of mass.
C)An object is represented in a free-body diagram by a word that says object.
D)An object is represented in a free-body diagram by having the mass labeled.
Clear answer
Answer: the answer is D
Explanation:
