Answer:
Because most cells are too small to be seen by naked eye.
Microscopes allowed scientists to observe Prokaryotic cells which make up Bacteria and Archaea. These cells are small and contain no membrane- bound organelles. It allowed them to observe Eukaryotic cells with a nucleus and membrane-bound organelles that perform different life functions.
Answer:
Microscopes are necessary to study cells because cells are microscopic. Because a cell is the smallest unit of life, this means that they can’t be seen by the naked eye. But using a microscope allows scientists to zoom in and see all parts of a cell. Therefore, scientists must use microscopes to study cells. Microscopes have helped us discover new things like bacteria, diseases, new species, and to study fossils. As microscopes improve we can see smaller and smaller cells.
Hope this helps!✌️
A student compares a sample of isooctane with some petrol. the student found that the isooctane boiled at 99°C while the petrol boiled between 45 and 95°C. which of these is a puse Substance? Explain ur answer.
Answer:
The isooctane
Explanation:
A pure substance is, according to Wikipedia, "a chemical substance is a form of matter having constant chemical composition and characteristic properties." That's a lot of words, but we just need to focus on some of them: "constant... characteristic properties." The properties of a pure substance always stay the same, no matter what.
The boiling point of a substance is one of its properties. It looks like the petrol boils at different points, between 45 and 95°C. The isooctane, on the other hand, boils consistently at 99°C. So, we can infer that the isooctane is the pure substance.
Hopefully that was helpful! If you need more questions answered, let me know. :)
24.) In humans animals and plants the DNA is found in the?
Answer:
chromosome
Explanation:
Answer:
Most of the DNA in all animals, humans, and plants is found in the cell nucleus. Humans, animals and plants contains both DNA and RNA in the cell nucleus and they have to be present in all because every organisms structure and function directly depends upon them.
Explanation:
Which of the following is the equation for wave speed?
Answer:
[tex]{ \boxed{ \mathfrak{ \: answer : \: { \bf{v = f \lambda}} }}}[/tex]
v is the wave speedf is frequencylambda is wave lengthwhat happens to the atoms during a chemical reaction
Answer:
Atoms get rearranged and make up different molecules. No atoms are created nor destroyed.
Explanation:
please helllllllllllllllllllllllllllllllp
So what you dos is the final temperature - the initial temperature. For example for 1) we have 88.5 celsius degrees - 78 celsius degrees = 10.5 celsius degrees.
A sturdy plant is placed in an airtight, transparent container. The entire experiment is then weighed. For 10 days, the plant grows inside the container. After 10 days, the container is weighed again. The air inside the container is pumped out and carefully analyzed.
What is true about the air inside the container and the mass of the experiment?
-The air is richer in carbon dioxide. The mass of the experiment has not changed
-The air is richer in oxygen. The mass of the experiment has changed.
-The air is richer in carbon dioxide. The mass of the experiment has changed.
-The air is richer in oxygen. The mass of the experiment has not changed.
Answer:
hi
Explanation:
bye
Heavy rains fill a reservoir, causing the dam that holds the water to break. As a result, the areas downstream are suddenly flooded. Which question would a
scientist seek to answer?
A. What will be the long-term effect of the flood on the plants and
animals in the area?
B. Who was responsible for the design flaw in the dam?
C. What changes in regulations are needed to prevent future dam
failures?
D. How much money should be spent to ensure dam safety?
ain the energy transformation that occurs when a hair dryer is plugged in and turned on.
Group of answer choices
Chemical energy transforms into electrical and sound energy.
Electrical energy transforms into mechanical and thermal energy.
Mechanical energy transforms into chemical and electrical energy.
Thermal energy transforms into electrical and gravitational energy.
Answer:
Mechanical
Explanation:
Since, this mechanical energy gets converted into thermal energy due to which hairs get dry. Thus, we can conclude that the energy transformation that occurs when a hair dryer is plugged in and turned on is that electrical energy transforms into mechanical and thermal energy.
What do all the molecules in the table have in common?
Answer:
They all consist of the same amount of protons, electrons, and neutrons in an element.
Explanation:
For example in water (H20) contains 1 atom of protons, 1 atom of electrons and 1 atom of neutrons.
In a compound, chemical energy is _______________ when bonds break.
a
absorbed
b
released
c
both A and B
d
neither A or B
An atom's Lewis dot structure has three dots. Which of the following elements could it be, and why? (4 points)
Group of answer choices
Aluminum, because it is in group 13 and has three valence electrons.
Lithium, because it is a group 1 element with three total electrons.
Magnesium, because it is in period 3 and has three valence electrons.
Potassium, because it is an alkali metal and has three inner shell electrons.
Answer : The correct option is, Magnesium because it is a group 2 element with two valence electrons.
Explanation :
Element = Calcium
Atomic number = 20
Electronic configuration of Ca =
Number of valence electrons in Ca = 2
The number of inner shell electrons in Ca = 18
This option is wrong because lewis-dot structure shows only valence electrons not inner shell electrons.
Element = Carbon
Atomic number = 6
Electronic configuration of C =
Number of valence electrons in C = 4
This option is wrong because only outermost p-sublevel electrons are not showing in lewis-dot structure.
Element = Lithium
Atomic number = 3
Electronic configuration of Li =
Number of valence electrons in Li = 1
This option is wrong because it has only 1 electron in outermost shell.
Element = Magnesium
Atomic number = 12
Electronic configuration of Ma =
Number of valence electrons in Ma = 3
This option is correct.
Lewis-dot structure : It is defined as the structure in which valence electrons of the atom is shown as dots.
ANOTHER EXPLANATION:
Answer: C. Magnesium, because it is a group 2 element with two valence electrons.
An atom's Lewis dot structure has two dots. Which of the following elements could it be, and why?
A. Calcium, because it is an alkaline earth metal with two inner shell electrons.
B. Carbon, because it has two electrons in its outermost p sublevel.
C. Lithium, because it is a group 1 element with two bonding electrons.
D. Magnesium, because it is a group 2 element with two valence electrons.
Explanation:
If you were to look at the periodic table magnesium would be in group 2. Since magnesium is in group 2 therefore it will have two valence electrons. Calcium is another possible answer because it is also in group two, but for this quiz it is incorrect. Lithium is incorrect because it is in group 1 and therefore it would only have 1 valence electron. Carbon is also incorrect because it is in group 14 so it would have 4 valence electrons. Hope this helps and makes sense.
Good Luck!!
Have a great day Studying!
The Lewis dot structure of an atom has three dots. With three valence electrons and belonging to group 13, which of the following elements may it be?
Are the elements of group 13 metals?The semi-metal boron (B) and the metals aluminum (Al), gallium (Ga), indium (In), and thallium (In) are all members of the boron family (Tl). The periodic table's fifth element, boron (Z=5), is found in Group 13. It is categorized as a metalloid because of its characteristics, which combine those of metals and nonmetals.
What traits does group 13 exhibit?The Periodic Table of Elements places these elements in Group 13 (XIII) of the p block. Metallic elements include thallium, gallium, indium, and aluminum. In their outermost shells, they each have three electrons shell with the valence electron configuration ns2np1 (one electron in the p orbital and a complete s orbital).
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.
What is considered a pure substance?
Answer:
A substance that has a fixed chemical composition throughout is called a pure substance such as water, air, and nitrogen. A pure substance does not have to be of a single element or compound.
Explanation:
Compound: A substance that contains more than one element
pure substance: is made up of one substance made up of only one type of molecule
What’s solubility need it for science
Answer:
the ability of a compound to dissolve
Explanation:
salt dissolves in water so it would be soluble.
oil does not dissolve in water so it is not soluble
MARKING BRAINLIEST :)
Which property has a trend similar to that of electronegativity?
A. First ionization energy
B. Atomic radius
C. Ionic radius
D. Atomic mass
Answer:
a
Explanation:
There are various kind of elements that are present in periodic table. Some elements are harmful, some are radioactive, some are noble gases. Therefore, the correct option is option A.
What is periodic table?Periodic table is a table in which we find elements with properties like metals, non metals, metalloids and radioactive element arranges in increasing atomic number.
Periodic table help a scientist to know what are the different types of elements are present in periodic table so that they can discover the new elements that are not being discovered yet.
Along period, electronegativity increases. along group electronegativity decreases. The same trend is followed by first ionization energy in periodic table.
Therefore, the correct option is option A.
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Hand warmers and instant cold packs use _____ that release or absorb thermal energy.
Answer:
Hand warmers and instant cold packs use Endothermic that release or absorb thermal energy.Hand warmers and instant cold packs use endothermic reaction that release or absorb thermal energy.
What is thermal energy?Thermal energy is defined as by virtue of its temperature, a system in a condition of thermodynamic equilibrium contains internal energy. Fossil fuels like natural gas, coal, and oil are examples of thermal energy sources. They also include solar heat, electric heat pumps, and geothermal heat. Thermal energy is a type of kinetic energy, which is energy brought on by motion, and is brought on by the motion of particles. Things have an interior temperature as a result of thermal energy, which can be detected with a thermometer.
Endothermic reaction is defined as the chemical processes that result in the formation of products when the reactants absorb heat energy from their surroundings. A chemical reaction or physical change is referred to as being endothermic when heat is absorbed by the system from the environment. An endothermic process causes the system to absorb heat from its surroundings, which causes the surroundings' temperature to drop.
Thus, hand warmers and instant cold packs use endothermic reaction that release or absorb thermal energy.
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Explain why sodium loses one electron and chlorine gains one electron in three or more sentences.
Answer:
Sodium and chloride form an ionic bond. Therefore the sodium atom loses one electron from its outer shell and the chlorine atom gains one electron. As this happens, the electron is transferred from the sodium atom to the chloride atom and so both atoms become ionic and have a full outer shell.
How does the concentration of ions in a strong acid differ from a weak acid?
Answer:
A strong base has a much smaller concentration of positive ions (hydrogen ions) and a much greater concentration of negative ions (hydroxide ions). The weak base has a much greater concentration of positive ions (hydrogen ions) and a much smaller concentration of negative ions ( hydroxide ions) = answer !!
Explanation:
Can someone give me Two methods for monitoring and minimizing a human impact on the environment?
During region C of the graph above the energy being absorbed is a. increasing the velocity of the water particles. b. increasing the distance between the water particles and reducing their phase energy. c. increasing the distance between the water particles and increasing their phase energy. d. decreasing the velocity of the water particles.
Answer:
Your answer would be B. Increasing the distance between the water molecules and increasing their phase energy.
Explanation:
Hope this helps you answer this question!
need help w this question
Answer:
ok you got it you just need to add.
Explanation:
add 5 times and she what you get.
Plz help ASAP
Dgdhhd
Answer:
Same As.
Explanation:
Mass will not increase or decrease because matter is not created or destroyed. The Law of Conservation of Mass states that the mass of a system must remain constant throughout. Energy is conserved.
A gas has a pressure of 1.51 atm and occupies a volume of 8 L. If the gas is compressed to a volume of 1.12 L, what will its pressure be, assuming constant temperature? Answer in units of atm.
Answer:
[tex]\boxed {\boxed {\sf 10.8 \ atm}}[/tex]
Explanation:
We are asked to find the new pressure of a gas after a change in volume. Since the temperature remains constant, we are only concerned with pressure and volume.
We will use Boyle's Law, which states that the volume and pressure of a gas are inversely proportional. The formula for this law is:
[tex]P_1V_1=P_2V_2[/tex]
The gas has an original pressure of 1.51 atmospheres and a volume of 8 liters.
[tex](1.51 \ atm)(8 \ L)=P_2V_2[/tex]
The volume is compressed to 1.12 liters and the new pressure is unknown.
[tex](1.51 \ atm)(8 \ L)=P_2 (1.12 \ L)[/tex]
We are solving for the new pressure, so we must isolate the variable [tex]P_2[/tex]. It is being multiplied by 1.12 liters. The inverse operation of multiplication is division. Divide both sides of the equation by 1.12 L.
[tex]\frac {(1.51 \ atm)(8 \ L)}{1.12 \ L}= \frac{P_2(1.12 \ L)}{1.12 \ L}[/tex]
[tex]\frac {(1.51 \ atm)(8 \ L)}{1.12 \ L}= P_2[/tex]
The units of liters (L) cancel.
[tex]\frac {(1.51 \ atm)(8 )}{1.12}= P_2[/tex]
Multiply the numerator.
[tex]\frac {12.08 \ atm}{1.12}= P_2[/tex]
[tex]10.7857143 \ atm = P_2[/tex]
Round to the nearest tenth. The 8 in the hundredth place tells us to round the 7 in the tenth place up to an 8.
[tex]10.8 \ atm \approx P_2[/tex]
The new pressure after the volume is compressed is approximately 10.8 atmospheres.
Which description is an example of the effects of rising temperatures?
Can someone help with this pls!!
Answer:
2
Explanation:
good vibes
Why does the atomic radius increase from top to bottom?
go to Russia and ask them. they know a lot about nukes
Explain why the number 1,085 is NOT a perfect square
1085 is a perfect square if the square root of 1085 equals a whole number. The square root of 1085 is not a whole number. 1085 is not a perfect square root.
Do you want to play again?
An object experiences a net force to the right that gives it an acceleration of 2.0 m/s2. If the net force is doubled then the new acceleration of the object will be ???
Answer:
The acceleration of an object as produced by a net force is directly proportional to the magnitude of the net force, in the same direction as the net force, and inversely proportional to the mass of the object.
Help on this question please
Answer:
Option 4
Explanation:
Velocity is the rate at which the position changes
The force on an object is given by the equation F= ma. In this equation, Fis
the force, mis the mass, and a is the acceleration. What is the force on an
object that has a mass of 540 kg and an acceleration of 2.3 m/s2?
Answer:
[tex]\boxed {\boxed {\sf 1, 242 \ N}}[/tex]
Explanation:
According to Newton's Second Law of Motion, force is the product of mass and acceleration.
[tex]F=ma[/tex]
In this formula, F is the force, m is the mass, and a is the acceleration.
The mass of the object is 540 kilograms and the acceleration is 2.3 meters per second squared.
m= 540 kg a= 2.3 m/s²Substitute the values into the formula.
[tex]F=(540 \ kg)(2.3 \ m/s^2)[/tex]
Multiply.
[tex]F=1242 \ kg*m/s^2[/tex]
Conver the units. 1 kilogram meter per second squared is equal to 1 Newton. Therefore, our answer of 1242 kilogram meters per second square is equal to 1242 Newtons.
[tex]F= 1242 \ N[/tex]
The force of the object is 1242 Newtons.
In the formation of an ionic compound a metal atom is most likely to __________ valence electrons
Answer:
To lose valence electrons.
Explanation:
