Answer:
A force between an object and the surface it's moving over.
Explanation:
hope this helps. . . <3
good luck! uωu
PLZ HELP i need it now
what do you mean by decimal number system
please give answer
for each type of geometry in the simulation, examine the resulting bond angles by clicking the show bond angles checkbox. based on your observations for each geometry, provide the bond angles at the indicated locations for the two-dimensional representations of the three-dimensional structures.
The bond angles in PCl5 are 90° and 180° respectively. The bond angle in NH4^+ is 109°.
Bond angles refer to the angle between two atoms bonded to the same central atom. Several factors such as electronegativity difference and presence or absence of lone pairs on the central atom all affect the bond angle.
For NH4^+, the indicated bond angle is 109° and the specie is tetrahedral. For the specie, SF6, the indicated bond angles are 90° and 180° respectively. For HCN, the indicated bond angle is 180°. For PCl5, the indicated bond angles are 90° and 180° respectively.Learn more: https://brainly.com/question/2192784
Elements in the same period in the same periodic table have the same ____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________
Elements in the same period have the same number of electron shells; moving across a period (so progressing from group to group), elements gain electrons and protons and become less metallic. This arrangement reflects the periodic recurrence of similar properties as the atomic number increases.
PLEASE MARK ME BRAINLIEST ANSWERER
11) When sodium metal is subjected to violet light, it causes the photoelectric effect. However, red light does not affect
the sodium. Explain this phenomena.
The maximum wavelength for which photoelectric effect occurs in sodium is 400 nm.
Photoelectric effect has to do with the ejection of electrons from a clean metal surface when energy is supplied in the form of light. All wavelengths of light are not capable of achieving photoelectric effect.
There exists a maximum wavelength that the incident rays must posses in order for photoelectric effect to occur. The maximum wavelength for which photoelectric effect occurs in sodium is 400 nm.
The wavelength of red light is around 625 - 740 nm which is far longer than the wavelength of violet light which is around 380 - 425 nm. Hence, when sodium metal is subjected to violet light, it causes the photoelectric effect but red light does not affect the sodium metal.
Learn more: https://brainly.com/question/865531
Which of the following is the best definition of deposition in geology?(1 point)
A:the creation of volcanic rock when liquid magma hits the ocean and cools
B:the mixing of many layers of sediment by wind, water or ice
C:laying down of sediment in layers carried by wind, water or ice
D:the creation of any metamorphic rock
Answer:
Deposition is the laying down of sediment carried by wind, flowing water, the sea or ice. Sediment can be transported as pebbles, sand and mud, or as salts dissolved in water.
What do all atoms in a period (horizontal rows) have in common?
Answer:
All of the elements in a period have the same number of atomic orbitals. For example, every element in the top row (the first period) has one orbital for its electrons. All of the elements in the second row (the second period) have two orbitals for their electrons.
hope this helps
Explanation:
Elements in the same period are those that are in a single horizontal line from left to right. They do not share the same type of chemical reactivity as seen in groups. They only real thing that these elements share in common is the same principal quantum number, or main energy shell.
Determine the pH of 7.53 x 10-4 mol/L calcium hydroxide solution
Answer:
pH = 11,17
Explanation:
[tex][OH^{-} ] = \frac{n_{OH^{-} } }{V} = \frac{2n_{Ca(OH)_{2} } }{V} = 2[ Ca(OH)_{2} ]\\[/tex]
[tex]Ca(OH)_{2}[/tex] → [tex]Ca^ {2+}[/tex] + [tex]2OH ^ -[/tex]
[tex]7,53.10^-4[/tex] → [tex]7,53.10^-4[/tex] → [tex]1,506^-3[/tex]
pOH = -log [[tex]OH^-[/tex]] = [tex]-log 1,506^{-3}[/tex] ≈ 2,822
pH = 14- pOH = 14-2,822 = 11,178
Question 1 (2 points)
Which option can be classified as a pure substance?
Question 1 options:
heterogenous mixture
solution
homogenous mixture
compound
Question 2 (2 points)
Law of conservation of mass states that:
Question 2 options:
matter is destroyed
matter does not change
matter is neither created nor destroyed
matter is created
Question 3 (2 points)
What is a property of bases?
Question 3 options:
all of the above
Sour taste
Slippery touch
Ability to form hydronium ions+
Question 4 (2 points)
Which property do solutions with low pH values have?
What does it mean to have a neutral pH? - Aseptic Health
Question 4 options:
have a -OH group
feels slippery
turns litmus paper blue
tastes sour
Question 5 (2 points)
How do the products of chemical reactions compare to their reactants?
Question 5 options:
The products often have completely different properties than the reactants.
The products are usually more toxic than the reactants.
The products usuallyhave more mass than the reactants.
The products usually have more atoms than the reactants.
Question 6 (2 points)
Which of the following is an example of a physical change?
Question 6 options:
Water freezing into ice.
A piece of wood burning.
A toy car rusting.
Zinc producing hydrogen gas when mixed with water.
Question 7 (2 points)
What might happen if you mixed a strong acid with an equally strong base?
Question 7 options:
You would see an explosive chemical reaction.
The base would destroy the acid.
You'd wind up with a pH-neutral salt and water.
The acid would destroy the base.
Question 8 (2 points)
In the equation shown, what are the reactants?
2H2+O2àH2O
Question 8 options:
Hydrogen and oxygen molecules (2H2 and O2 )
Ice crystals
Hydrogen atoms (H)
Water molecules (H2O)
Question 9 (2 points)
Which phrase most accurately describes a chemical change?
Question 9 options:
A change in form
A change in taste
A change on the molecular level
A change in appearance
Question 10 (2 points)
What does it mean when there is a physical change?
Question 10 options:
A new substance has been formed.
Matter has changed from one substance into a new substance.
Matter has changed size, shape or form
Matter has changed on the molecular level.
help pls ill give 20 points!
Answer:
I didn't KNOW WHAT IS THE ANSWWR OF YOUR QUISTION IM SO SORRY
Explanation:
I WANT TO INTRODUCE SELF TO YOU CAN I
Lead has a density of 11.29 g/mL. If you had 186 g of lead, what would its volume be?
EASY QUESTION (PLEASE HELP THE INTERNET ISN'T SUCH A BIG HELP RIGHT NOW)
Things microscopes have helped scientists discover about cells.
(No links plz)
Answer:
Microscopes allowed scientists to observe Prokaryotic cells which make up Bacteria and Archaea.
how many electrons need to be lost or gained by Ca to attain noble gas electron configuration?
Answer:
six electrons need to be gained
Explanation:
Calcium has two valence electrons. To have a stable amount of valence electrons, or to attain noble gas electron configuration, an element needs to have eight valence electrons. Now, it's just a simple math problem. How many more valence electrons does calcium need to get to eight? It needs six, since eight minus two is six.
Hopefully that's helpful! :)
Which of the following is/are considered alcohols?
a CH3OH
b CH3CH2OH
C CH3CH2CH2OH
d All of the above
Answer: THE ANSWER IS D
Explanation:
an alcohol is a hydrocarbon chain with an hydroxyl group (OH)
A, B, AND C ARE ALL ALCOHOLS, SO THE ANSWER IS D
A clasping handshake may be used as an analogy for an enzyme-catalyzed reaction because it represents the specific manner in which an enzyme ________. folds to form secondary and tertiary structures interacts with water binds substrate is denatured by low pH
A clasping handshake is similar to the way in which enzymes bind to substrates in enzyme-catalyzed reactions.
Enzymes are biological catalysts that speed up the rates of biological reactions by lowering the minimum energy required by reactants in order to arrive at products.
Enzymes are able to achieve this feat by substrate-enzyme binding. The substrate binds to the enzyme in its active site, becomes products, and the products are released from the active site of the enzyme. Thus, the enzyme is free for the binding of another substrate.
More on enzyme-catalyzed reactions can be found here: https://brainly.com/question/6658074
What were the first 5 planets that were observed? Why were those the only ones? Help pls!
Darwin observed __________________ types of mockingbirds and finches lived in different island environments.
Answer:
Darwin observed many different types of mockingbirds and finches lived in different island environments.
Review the information from the documents you read for this assignment. Use what you learned to answer the following question. What were the major effects of a dust storm? Give your answer in at least four sentences.
Answer:
what people experienced during a dust storm
how people reacted to a dust storm
what people did after a dust storm
Explanation:
i passed
Answer:
what people experienced during a dust storm
how people reacted to a dust storm
what people did after a dust storm
Explanation:
What is the average acceleration of the car between 24 and 40 seconds? Include the correct units.
Answer:
16
Explanation:
40 - 24 16
convert 120 mm to feet
Answer:
0.393701
Explanation:
Study the chemical equation.
Na + Cl2 → NaCl
Is the chemical equation properly balanced?
the electron configuration of an element describes _____.
Answer:
here
Explanation:
This is the electron configuration of the element carbon.
JWhat type of evidence is gathering information through your senses or using scientific tools?
Predictions
Results
Scientific research
Observations
What are the four groups of carbon compounds found in living things?
In the chloroplast, energy in sunlight is passed around different chlorophyll molecules until it reaches a specific chlorophyll molecule that can transfer energy in sunlight to an energized electron. This chlorophyll molecule is called the accessory pigment. electron-carrier molecule. nucleus. photoelectric point. reaction center.
Answer:In the chloroplast, energy in sunlight is passed around different chlorophyll molecules until it reaches a specific chlorophyll molecule
Explanation:
Answer: In the chloroplast, energy in sunlight is passed around different chlorophyll molecules until it reaches a specific chlorophyll molecule
describe the development of the theory of atomic structure
this question is worth 6 marks
how many valence electrons are there in a magnesium atom?
Answer:
Magnesium has 2 valence electrons.
why are there no elementary substances that have the ionic bond?
This problem is asking for the reason behind the nonexistence of elementary substances with ionic bonds. First of all, it is necessary to bear to mind that the definition of the type of bond in a compound depends on the difference electronegativity that is present between two of the atoms composing it.
For instance, in binary salts, such as KCl, NaCl, KBr and so on, we are able to know these are all ionic because they are composed by a metal and a nonmetal, which have the smallest and largest electronegativities, so that the difference electronegativity is large enough to produce an ionic bond.
In contrast, elementary susbtances, such as liquid bromine (Br2) and gases such as H2, N2, Cl2, F2 and O2, since they are all nonmetals and the same type, the electronegativity difference will be 0 and therefore, they will not be ionic but covalent.
Learn more:
https://brainly.com/question/15105831https://brainly.com/question/14509196Atoms: SC.8.P.8.7
Match the definition to proper definition:
Term:
Definition:
1. Atoms
A.Positive subatomic particles found in the
nucleus of the atom
2. Neutron
B. Negative subatomic particle found in the cloud
3. Proton
C. Substance that has no electrical charge
4. Nucleus
D. Basic building block of all matter
5. Electron cloud
E. Substance that consists of only one type of ato,
6. Electrons
F. Center of an atom with a positive charge
G. Outside of the atom with a negative charge
7. Element
Answer:
1 = D
2 = C
3 = A
4 = F
5 = G
6 = B
7 = E
how might rising atmospheric co2 concentrations lower the ph of the oceans?
Explanation:
As CO2 concentrations rise, excess CO2 is absorbed by the oceans. CO2 in the oceans can react chemically with water to form acid. ... The difference in pH units between two acidic solutions is three.
what is the mass percent of hydrogen in water
Answer:
11.11%
Explanation:
The percentage of an element in a compound is 100 times the fraction, so for water the mass percent hydrogen is 11.11%
Hope this helps :)