Answer:
23 because the atomic number is base on protons and electrons and the neutrons is 20 hope it help
at what temperature does a solid turn into a liquid
Answer:
0°C
Hope this helps Do mark as brainliestAnswer:
a little over 0 degrease cel
Explanation:
Which describes the motion of the car as shown by the graph?
A) travels at a constant speed
B) not moving
C) changing directions
D) speeding up
Burning is a type of_________reaction.
O replacement
O decomposition
O synthesis
O combustion
Answer:
Combustion
Explanation:
Happy Halloween!
Which of the following is an irreversible physical change?
a) melting a piece of lead
b) sharpening a pencil
c) dissolving sugar into water
d) boiling water
Answer:
b) sharpening a pencil
Explanation:
If you melt lead, boil water, or dissolve sugar in water, you can return all of them back to their original state. If you sharpen a pencil, you can't reattach the shavings as they were originally.
You may put all of them back to their original states by melting lead, heating water to a boil, or dissolving sugar in water. You cannot rejoin the shavings from a sharpened pencil in their original position. Thus, option B is correct.
What is irreversible physical change?When something changes physically but not chemically, it has undergone an irreversible physical alteration that cannot be reversed.
Sharpening a pencil is a perfect example of an irreversible physical change. The wood turns to dust when you sharpen it. Just in a different shape, it is still wood. That wood dust cannot be transformed back into a pencil.
You cannot put a piece of paper back together the same way it was before you tore it if you tear it into tiny pieces.
An irreversible alteration is one that cannot be undone or that cannot be returned to its original state, such as when milk turns into curd, iron turns rusty, paper burns, food is cooked, etc.
Therefore, sharpening a pencil is an irreversible physical change
Learn more about irreversible here:
https://brainly.com/question/24111037
#SPJ2
mL? PLEASEEE HELP
What is the answer
In a longitudinal wave, particle displacement is
from google, so I think the answer to that question is the second one
The heart is a large
________________
that pumps the blood
throughout the body.
Record the length of the object shown.
Answer: 7.26 mm
I did the test already.
PE = mgh, solve for m
Answer:
P.E. = mgh, where m is the mass in kilograms,
Answer:
[tex]m = \frac{PE}{gh} [/tex]
Explanation:
[tex]if \: PE = mgh \\ then \to \\ m = \frac{PE}{gh} [/tex]
♨Rage♨
The millions of fossils that scientists have collected are called the fossil __.
Answer:
record
Explanation:
(b) Define, in terms of oxidation state, the Oxidizing agent
a substance which gains oxygen
a substance whis lose hydrogen
a substance which experiences a decrease in oxidation state
a substance which experiences an increase in oxidation state
Answer: a substance whis lose hydrogen
Explanation:
Sodium + oxygen
What colour is the flame produces
Answer:
Orange
Explanation:
I used google my b
Answer:
ORANGE
explanation:
Small pieces of sodium burn in air with often little more than an orange glow. Using larger amounts of sodium or burning it in oxygen gives a strong orange flame.
The reaction in which methane is burned, CH4 +202 --> 2H20 + CO2, is an example of a
combustion reaction
O synthesis reaction
O decomposition reaction
O precipitate reaction
Answer: Combustion
Explanation:
Methane gas or natural gas is the hydrocarbon that reacts with oxygen as shown below: CH4 + 2O2 → CO2 + 2H2O There are two types of combustion reactions: complete and incomplete combustion. Therefore there are four products, carbon dioxide, water, carbon, and carbon monoxide.
NEED HELP PLEASE
Part A:
In your own words, describe the process of a physical change.
Part B:
What is the difference between a physical change and a chemical change? Give an example of each.
Answer:
Part A:
A physical change is a change of a substance from one form to another without changing its composition.
Part B:
A physical change is a change of a substance from one form to another without changing its composition. Example: A balloon deflating into its original form.
A chemical change occurs, one substance combines with another substance to make something completely new. Example: Making and baking a cake.
What is the density of an object that has a mass of 62.4 grams and a volume of 7.6 cm 3 ?
How many electrons does each lithium atom provide to the voltaic cell?
A. 1
B. 2
C. 3
D. 4
Answer:
c. 3 electrons
Explanation: for the element of LITHIUM, you already know that the atomic number tells you the number of electrons. That means there are 3 electrons in a lithium atom.
Define a force.......
Answer:
Gravitational Force.
Gravitation is the agent that gives weight to objects with mass and causes them to fall on the ground when dropped.
Answer:
A force is the strength or energy as an attribute of physical action or movement.
Explanation:
In smaller words, a force is a form of energy caused from a push or a pull on an object. A force happens when two objects interact with each other. For example, when you throw a ball you are using force.
Hopefully this helps im sorry if i got it wrong im kinda dumb... XD
Define the concept of Energy in your own words
Answer:
In general, the word energy refers to a concept that can be paraphrased as "the potential for causing changes", and therefore one can say that energy is the cause of any change. The most common definition of energy is the work that a certain force (gravitational, electromagnetic, etc) can do. Due to a variety of forces, energy has many different forms (gravitational, electric, heat, etc.) that can be grouped into two major categories: kinetic energy and potential energy. According to this definition, energy has the same units as work; a force applied through a distance. The SI unit of energy, the joule, equals one newton applied through one meter, for example. Energy has no direction in space, and is therefore considered a scalar quantity. Energy is a conserved quantity, meaning that it cannot be created or destroyed, but only converted from one form into another. Thus, the total energy of the universe always remains constant. One form of energy can be readily transformed into another; for instance, a battery converts chemical energy into electrical energy.
Explanation:
Atomic number is equal to the number of electrons in an atom?.
Answer:
true I think not sure
Explanation:
HELPPP PLEASEEE!!! calculate the energy of radiation with a wavelength of 432 nm
What is the rule of zero charge?
Answer:
The nonmetal atoms accept electrons and form ions with a negative charge, called anions. When an ionic compound forms, the total charge on the atoms adds up to zero. This is known as the rule of zero charge.
Explanation:
Classify the following chemical reaction
3 C + 4H2→ C3 H8
Answer:
Synthesis Reaction
General Formulas and Concepts:
Synthesis Reactions: A + B → AB
Decomposition Reactions: AB → A + B
Single-Replacement Reactions: A + BC → AB + C
Double-Replacement Reactions: AB + CD → AD + BC
Explanation:
Step 1: RxN
3C (s) + 4H₂ (g) → C₃H₈ (s)
We see here that we are combining 2 elements to form a compound.A would be C, B would be H₂, and C₃H₈ would be ABTherefore, we have a Synthesis ReactionWhat advances in technology helped usher in the scientific revolution? Choose the best answer.
1.The landing on the Moon by Apollo brought about the scientific revolution.
2.Discoveries by scholars in the Catholic Church revolutionized scientific knowledge.
3.The discoveries by ancient Greek, Muslim and Chinese scientists.
4.The discovery of optics gave scientists instruments such as microscopes and telescopes.
Answer:
The discovery of optics gave scientists instruments such as microscopes and telescopes.
Explanation:
The period between the 16th-8th century was called the period of the scientific revolution. At this time, the foundations of our modern science was laid.
One of the characteristic of this period was the emphasis on the scientific method which upheld results from reproducible experiments.
Nicolaus Copernicus, Francis Bacon and Isaac Newton were leading names in this period.
It was within this period that the discovery of optics gave scientists instruments such as microscopes and telescopes and scientific examination of the celestial bodies was launched.
Explain why warm air temperature has lower air pressure than cold air?
Answer:
Differences in temperature cause differences in air density. Warmer air is less dense than cold, which is why warm air tends to rise and cold air sinks.
temparature affects particles. warm particles are more spread out.
Explanation:
. Being acted on by gravity, colder, denser air weighs more and exerts greater pressure per unit area.
which element would have properties most like arsenic (As)? Te Ge P Se
Answer:
P
Explanation:
What element would have this electron configuration:
1s22s22p5
Which of the following has a higher electronegativity oxygen or selenium?
Answer: Oxygen
Explanation: Oxygen has more ionisation energy and Oxygen has a small size which makes it more electronegative.
Sugar is added to iced tea and the contents are stirred until all of the sugar dissolves. How would the tea now be classified?
What is involved in weathering?
Answer:
the answer is water.Hope this helps
Select the correct answer.
In which situation is no work considered to be done by a force?
A.
when the angle between the force and displacement is 180°
B.
when the angle between the force and displacement is 90°
C.
when the angle between the force and displacement is 45°
D.
when the angle between the force and displacement is 0°
Answer:
Explanation:
when the angle between the force and displacement is 0