Answer:
A. wearing sunglasses to to protect eyes from UV rays
Explanation:
Your eyes are outside of your body, meaning external. All the other choices deal with internal organs.
Give 2 reasons why is copper used for electrial wires
Answer:
Copper electrical wires are safer to use than wires made of most other conductive metals because they are resistant to heat. As you can see, copper is the preferred metal for electrical wires for several reasons. It has high electrical conductive; it's inexpensive; it's ductile; and it's thermal resistant.
How did modern scientists experiment with Van Gogh's paints to determine their chemical reactions?
1. They used X-ray analysis.
2. They used litmus testing.
3. They burned the paint to examine what elements were left after the chromium was burned off.
4. They studied the density of modern yellow paint to that of 100-year-old paint.
Answer:
I think the answer is A - they used X-ray analysis.
Explanation:
Answer:They used X-ray analysis
Explanation:
It’s in the text
Please help I will give brainliest
Answer:
Explanation:
c. - vaccine
b. - immunity
d. - phagocyte
f. - b cell
e. - t cells
a. active immunity
(NH4)2SO4. How many N are there?
Which formula represents a
polar molecule
containing polar covalent bonds?
A. H2O
B. CO2
C. NaCL
D. Cl2
Answer:
A. H2O
Explanation:
Let us first define the three types of bonds:
1. Nonpolar Covalent: electronegativity difference < 0.4
2. Polar Covalent: electronegativity difference between 0.4 and 1.8
3. Ionic: electronegativity difference > 1.8
This will help us eliminate choices C and D:
-NaCl has a electronegativity difference of 3.0 - 0.9 = 2.1 (ionic bond)
-Cl2 has a electronegativity difference of 3.0 - 3.0 = 0 (nonpolar covalent bond)
However, we still have two more options, A and B, but they are not diatomic for us to use the electronegativity differences with.
We must now consult their geometries. Because CO2 has a linear geometry (O=C=O), the two sides will cancel each other out, resulting in a nonpolar covalent bond. At this point, by process of elimination, we can already determine the answer to be A. H2O. We can verify this by looking at the geometry of H2O, which is bent (H-O-H; imagine the O is above the H's, I cannot draw it in this response). H2O's bent geometry classifies it as polar covalent; the electrons are slightly more attracted towards the O, the more electronegative element. Side note: this makes the O slightly more negative in charge, whilst the H's are slightly more positive in charge.
P.S. I apologize for not being able to draw and demonstrate that last paragraph, but I hope you get a general idea. You can search up the "H2O geometry" and "CO2 geometry" to get a better idea! :)
H₂O represents a nonpolar molecule containing polar covalent bonds. Hence Option (A) is correct
What is Polar Covalent Bond ?A polar covalent bond exists when atoms with different electronegativities share electrons in a covalent bond.
Consider the hydrogen chloride (HCl) molecule. Each atom in HCl requires one more electron to form an inert gas electron configuration.
Water (H₂O), like hydrogen Chloride (HCl), is a polar covalent molecule. When we look at a diagram of water , we can see that the two hydrogen atoms are not evenly distributed around the oxygen atom
Water (H₂O) is polar because of the bent shape of the molecule. The shape means most of the negative charge from the oxygen on side of the molecule and the positive charge of the hydrogen atoms is on the other side of the molecule.Thus, This is an example of polar covalent chemical bonding.
Therefore, H₂O represents a nonpolar molecule containing polar covalent bonds. Hence Option (A) is correct
Learn more about bonding here :
brainly.com/question/1603987
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An elephant and a parakeet standing on ledge will have a different amount of potential energy because of their . this is for science actually
Answer:
Mass
Explanation:
Electrical energy is the amount of energy that an object contains due to kinetic energy
Answer:
The energy an object has due to its motion is called kinetic energy. Factors Affecting Kinetic Energy: the kinetic energy of an object depends on both its speed and its mass. The faster an object moves, the more kinetic energy it has.
Explanation:
(25 points)Diesel fuel is used in the engines of the machines and trucks at the quarry. Which of these is the main energy transformation as the fuel is used by the engines
1 Electrical energy is converted to heat energy.
2 Heat energy is converted to potential energy.
3 Electrical energy is converted to kinetic energy.
4 Chemical energy is converted to kinetic energy.
what is the answer PLEASE HELP!!
Answer:
the water displaced will not help the student find the correct volume because you can not accurately calculate it. you have to get the water when it is settled then you place the wood in.
Explanation:
Find a periodic table and look for the atomic mass of sodium, Na. What is it?
Answer:
Atomic mass: 22.989769 u
Explanation:
23.When an atom absorbs energy
a.One or more electrons will move to a higher energy orbit
b.One or more electrons will move to a lower energy orbit
c.Colored light is produced
d.There is an explosion
Answer:
a.One or more electrons will move to a higher energy orbit
Explanation:
Absorbing energy means that the electron gets excited and jumps to a higher level.
3. When two atoms are combined what do they make?
Answer:
When two or more atoms chemically bond together, they form a molecule. Sometimes the atoms are all from the same element. For example, when three oxygen atoms bond together, they form a molecule of ozone (O3). If a molecule forms from atoms of two or more different elements, we call it a compound.
Explanation:
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Scott and his classmates were looking at an animal cell under a microscope. They are trying to locate the cell's DNA, which is found in its chromosomes. Where should Scott look to find the chromosomes?
In the mitochondria
In the cell nucleus
In the cytoplasm
In the cell vacuole
How many moles of ammonia gas are produced from 3.6 moles of hydrogen gas and excess nitrogen gas?
Answer:
If so, the limiting reagent of Nitrogen would allow 16 moles of Ammonia to be produced.
Explanation:
Predict the empirical formulas of the ionic compounds formed from the following pairs of elements.
Mg and Cl
Cs and Br
Ga and I
Na and O
Sr and F
Ca and P
Explanation:
MgCl2
CsBr2
Na2O
SrF2
CaP2
After which reaction. is there solid left in the reaction chamber
a)Sodium Azide
b)Ammonium Nitrate
c)Nitroglycerin
d)Both A & B
Answer:
B.
Explanation:
If we add more SO2 gas to the reaction chamber. To the left. The reaction would drive
backwards to re-establish equilibrium (more reactants made).
The area of a telescope lens is 6.668 × 103 mm2. What is the area in square feet (ft2)? Enter your answer in scientific notation
Answer:
[tex]7.13\times 10^{-2}\ ft^2[/tex]
Explanation:
The area of a telescope lens is 6.668 × 10³ mm²
We need to convert the area in ft².
We know that,
[tex]1\ mm^2=1.07\times 10^{-5}\ ft^2[/tex]
It means,
[tex]6.668 \times 10^3\ mm^2=6.668 \times 10^3\times 1.07\times 10^{-5}\ ft^2\\\\=0.0713\ ft^2[/tex]
or
[tex]0.0713\ ft^2=7.13\times 10^{-2}\ ft^2[/tex]
So, the required answer is [tex]7.13\times 10^{-2}\ ft^2[/tex].
What valence electron number do they all have in common
Questions and answer options are on ( Picture )
remember pick 2 answers it says
help :(
ZOOM IN if needed
Answer:
The answer is A
Explanation:
I dont see any claim
What is the total magnification if we using objective lens 4x and our eyepiece (ocular) lens is 10x
40x
100x
400x
1000x
how does plants react with no scratch?
Answer:
You see, plants need energy to grow and grow and grow. They use energy from sunlight to make a simple sugar, glucose. Whenever the plant needs energy, it can chomp a little glucose off of the starch.
without energy it wont get energy/food so it will eventually die
Explanation:
What type of chemical reaction is the following reaction:
carbon monoxide and oxygen yield carbon dioxide
Answer:
decomposition reaction
Carbon Tetrahydride reacts with Oxygen gas to form Carbon Dioxide gas and Dihydrogen Monoxide gas.
Explanation:
sodium hydrogen carbonate is heated after heating which substance is form??? and what is the colour of the substance
You're invited to a hot tub party! Being the science geek that you are, you decide to calculate the amount of mL in the 650.0 gallon hot tub!
Answer:
cool but can we have a little bit bigger
Explanation:
Describe what happens to a liquid's molecules as it boils and changes into a gas.
Answer:
the particels becomes loose and wild, making gas happen when it is heated up
Liquids evaporate faster as they heat up and more particles have enough energy to break away. The particles need energy to overcome the attractions between them. At this point the liquid is boiling and turning to gas.
acid+base->salt+water
What type of reaction is this?
Answer:
The reaction of an acid with a base is called a neutralization reaction. The products of this reaction are a salt and water.
Answer:
Neutralization reaction
Explanation:
Neutralization reaction it the reaction of acids and bases that form salt and water
hope it's helpful ❤❤❤❤
THANK YOU.
Calculate the vapor pressure (in torr) of a 35°C solution of ethanol and propanol where the mole fraction of propanol is .75.
Assume ideal behavior.
P°ethanol = 100 torr
P°propanol = 36 torr
Answer:
i wish i know
Explanation:
What would be the most likely explanation if none of the tested paint samples had turned brown?
1. The reaction was not actually caused by UV light.
2. The reaction only happens in real sunlight, not artificial.
3. The paint behaves differently on a canvas than it does in a laboratory.
4. None of the tested mixtures matched the chemical composition of Van Goghs paint.
Answer:4/d
Explanation:
i did this before
CAN SOMEONE PLZ HELP ME ON THIS
Answer:
Q1. C
Q2.ring number 1 is 2
ring number 2 is 8 and
ring number 3 is 18
Q3. p can contain 6 electrons max
and d can contain 10 electrons max
Q4. D
When an electron in an atom moves from high to low
energy levels:
a alpha particles are emitted
b gamma rays are emitted
c energy is emitted as electromagnetic radiation
d energy is absorbed
Answer:energy is emitted as electromagnetic radiy
Explanation:
