Answer:
5,18*10^{24}
Explanation:
N=n*Na
N=8.6*6.02*10^{23}
N=5,18*10^{24}
How do you know when a redox equation is balanced?
cell are the blank unit of all living organisms
what is an example of a problem that could be solved by applying knowledge of the behavior of light
Answer:
The application of reflection in the use of the microscopes.
Explanation:
Reflection is one of the properties of light. Reflection is a phenomenon whereby light waves hitting a surface is bounced off. Reflection helps us to see light and colors. This behavior of light is harnessed in the design of the microscope.
The light reflected by the microscope helps the researcher to view the specimen in his slide. Also, the mirrors placed in measuring devices reflects light that helps an observer to take an accurate reading.
Something that helps us to understand things that are too large or too small are called A. atoms B. molecules C. models D . compounds
Heeeeeellllppp, Iiiimmm sssooo stttuuuccckkk!
Answer:
I think it would be D. None of the above
Explanation:
why I think this is because none of the answers really adds up to it
why do animals need carbohydrates in their diets
Answer:
Carbohydrates are energy-providing feed components composed of carbon, hydrogen, and oxygen. They should make up about 75 percent of an animal's diet. The energy they provide powers muscular movements. Carbohydrates also produce the body heat that helps keep the animal warm.
A student is studying the ways different elements are similar to one another. Diagrams of atoms from four different elements are shown below. Nucleus Nucleus Atom 1 Atom 2 Nucleus Nucleus Atom 3 Atom 4
Answer:
atom 1 and atom 2
Explanation:
Why is overuse of resources a problem ?????
Answer: the overuse of resources will lead to a decline of the resources, the question was a little non specific so this was the best I could do :)
Explanation:
10pts! Will give brainllest! But please make sure your answer is correct.
Which of the following is true about weight and mass?
A.Your weight and mass are the same
B.Your mass would be more on Jupiter because it has more gravitational force.
C.Your weight would be greater on Jupiter because it has more gravitational force.
D.Your weight would be greater on the moon because it has more gravitational force.
Answer:
B. your mass would be more on jupiter because it has more gravitational force.
Explanation:
good luck must be a test
Question 1 of 10
What do biologists study?
A. Living things
B. The properties of light
C. The properties of matter
D. How matter and energy interact
SUBMIT
Answer:
A
Explanation:
Biology is the study of living things.
what is the generic equation for a combustion reaction?
Answer:
The generic equation for a combustion reaction is AB + O2 à AO + BO
Explanation:
An unknown substance with a mass of 83 grams absorbs 1,108 J while undergoing a
temperature increase of 11 °C. What is the specific heat of the substance?
Look at picture
ASAP please will mark as brainlist don’t got much time
Answer:
The specific heat of the substance is 1.21 [tex]\frac{J}{g*C}[/tex]
Explanation:
Calorimetry is the measurement and calculation of the amounts of heat exchanged by a body or a system.
There is a direct proportional relationship between heat and temperature. The constant of proportionality depends on the substance that constitutes the body as on its mass, and is the product of the specific heat by the mass of the body. So, the equation that allows calculating heat exchanges is:
Q = c*m*ΔT
where Q is the heat exchanged by a body of mass m, made up of a specific heat substance c and where ΔT is the temperature variation.
In this case:
Q=1108 J c= ? m= 83 g ΔT= 11 CReplacing:
1108 J= c*83 g* 11 C
Solving:
[tex]c=\frac{1108 J}{83 g* 11 C}[/tex]
c= 1.21 [tex]\frac{J}{g*C}[/tex]
The specific heat of the substance is 1.21 [tex]\frac{J}{g*C}[/tex]
what is 412.12 reduced to two significant figures?
Answer: 410
Explanation:
Drop the retaining numbers 1 and 2 after the decimal and then round the 2 in 412 to 0 because any number less than 5 rounds to 0. 0 shouldn’t count as a sig fig.
What is an energy
transformation?
A. When energy is destroyed
B. When energy changes from one form to
another
C. When energy is created
D. When energy is lost
bron
Answer:
B. When energy changes form one to another.
Explanation:
Energy transformation, also known as energy conversion, is the process of changing energy from one form to another. In physics, energy is a quantity that provides the capacity to perform work or provides heat.
Please help!! And quick 3. Which team will push the box farther?
Team 1 Team 2 5 N
5 N
5 N 5N
12 N
I
Answer:
team 25 N because the force is more
HELP ASAP!
Which type of molecule provides cells with energy?
Carbohydrate
Nucleic acid
Protein
Water
Answer:
ATP
Explanation:
ATP is the most abundant energy carrier molecule in cells.
basically nucleic acid
Which is a reason that a chemical engineer would use a rate law for a reaction in a chemical plant?
A. to calculate the amount of product that would form
B. to find out which reactant would be used up fastest
C. to see how a change in a reactant concentration would affect the speed of the reaction
D. to determine how to adjust the concentrations of reactants to make the correct product
Explanation:
to see how a change in a reactant concentration would affect the speed of the chemical reaction
what refers to the effect of gravity
on an
object?
A. mass
B. matter
thing
C. volume
D. weight
Answer: D
Explanation:
Weight by definition is mass multiplied by the acceleration of gravity. So, weight is the force of gravity
What is the difference between endothermic and exothermic reaction (shortest answer)
Answer:
An exothermic process releases heat, causing the temperature of the immediate surroundings to rise. An ethothermic process absorbs heat and cools the surroundings. Hope this helped.
The easiest way to explain endo and exothermic reactions are that endothermic reactions absorb energy and exothermic reactions release energy.
The way I remember this is that with exothermic reactions, the heat exits. Endothermic is just the opposite.
Hope this helps :)
What is the concentration of a salt water solution with 15 grams of salt in 100 mL of water?
A. 10%
B. 5%
C. 20%
D. 15%
This problem is providing the mass of salt, 15 g, that is dissolved in 100 mL of water, so its concentration is required and found to be 15 % according to the following calculations:
By mass percent:In chemistry, units of concentration in solutions are used to represent the relative amount of a solute that is dissolved in a solvent. Thus, in this case, we refer to a salt-water solution, whose concentration is calculated via:
[tex]\% m=\frac{m_{salt}}{m_{water}}*100\%[/tex]
In such a way, given the mass of salt, 15 g and volume of water, or solution, 100 mL, one obtains the following:
[tex]\% m=\frac{15g}{100g}*100\% \\\\\% m=15\%[/tex]
Learn more about by mass percent: https://brainly.com/question/5394922
Answer:
D) 15%
Explanation
PLS HELP ASAP Solar energy causes most of the water ___________________ on Earth’s surface?
Please answer this question ASAP
Salts of metals can be prepared by reacting a metal with an acid to produce the
salt and the gas hydrogen. Describe the test to show that the gas is hydrogen.
(2 marks)
Answer:
put a test tube over the opening, remove it and quickly put a lit splint near the mout or in the tube. if you hear a squeaky pop it is hydrogen.
Explanation:
hydrogen ignites in air.
To prepare 800mL of 1M phosphate buffer of pH 7.2 (PKa=7.1), by using salt = K2HPO4 and acid = KH2PO4, the quantity of salt required is
Answer:
78.04g of 0.448 moles must be added
Explanation:
Using H-H equation we can find the pH of the buffer:
pH = pKa + log [A⁻] / [HA]
Where pH is the pH of the buffer = 7.2
pKa = 7.1
[A⁻] = [K₂HPO₄]
[HA] = [KH₂PO₄]
Replacing:
7.2 = 7.1 + log [K₂HPO₄] / [KH₂PO₄]
0.1 = log [K₂HPO₄] / [KH₂PO₄]
1.2589 = [K₂HPO₄] / [KH₂PO₄] (1)
And as the concentration of the buffer is:
1M = [K₂HPO₄] + [KH₂PO₄] (2)
Replacing (2) in (1):
1.2589 = 1M - [KH₂PO₄] / [KH₂PO₄]
1.2589 [KH₂PO₄] = 1M - [KH₂PO₄]
2.2589 [KH₂PO₄] = 1M
[KH₂PO₄] = 0.44M
And [K₂HPO₄] = 0.56M
In 800mL = 0.8L:
0.8L * (0.56mol / L) = 0.448 moles K₂HPO₄. The mass is -Molar mass K₂HPO₄: 174.2g/mol-:
0.448 moles * (174.2g / mol) =
78.04g of 0.448 moles must be addedWhat is Redox reaction? What is oxidized, reduced, oxidizing, and reducing agent?
Answer:
Explained below.
Explanation:
- Redox reaction is defined as any type of chemical reaction whereby the oxidation number of a participating chemical atoms/elements undergo changes.
- The atom that is oxidized is the one that has an increase in it's oxidation number.
- The atom that is reduced is the one that has a decrease in its oxidation number.
- The reducing agent is defined as the atom that is oxidized.
- The oxidizing agent is defined as the atom that is reduced.
-HELP-
How many molecules are contained in 125 grams of oxygen gas (O2)?
Answer:
62.50
Explanation:
I divided the 125 in the result is 62.50 but it is considered a 62.
never mine:)
[tex]125gms[/tex] of oxygen gas contains [tex]2.35\times 10^{24}[/tex] molecules of oxygen.
The molecular weight of oxygen[tex]=16[/tex]
Therefore,[tex]O_2=2\times 16\\=32[/tex]
No.of Moles of oxygen in 125g is,
[tex]\frac{125}{32}=3.9 g[/tex]
1mole of oxygen contains [tex]6.023\times10^23 molecules[/tex]
No.of oxygen molecules in 3.9 g of oxygen is,
[tex]3.9 \times 6.023 \times10^23=2.348 \times 10^24[/tex]
Which can be roundoff and written as [tex]2.35 \times10^{24}[/tex]
Therefore, 125gms of oxygen gas contains [tex]2.35 \times10^{24}[/tex] molecules of oxygen.
Learn More: https://brainly.com/question/25261193
A more reactive metal displaces a less reactive metal from salt solution. Such reactions are called:
Answer:
Displacement Reaction.
Answer:
displacement reaction
Which statements about salt water are true? Check all that apply.
Salt water contains minerals other than salt.
Fresh water is heavier than salt water.
Objects float more easily in oceans than in lakes or rivers.
The temperature of ocean water is affected by the depth of the water.
The temperature of ocean water is affected by the ocean’s location.
Salt water contains minerals other than salt.
The temperature of ocean water is affected by the depth of the water.
The temperature of ocean water is affected by the ocean’s location.
Objects float more easily in oceans than in lakes or rivers.
These are all of the true answers
Answer:
First one and the last three
Explanation:
hope it helps
Is it better for people to learn from others, or is it better for people to learn on their own? {thesis statement} {subject: Writing}
Answer:
on your own?
Explanation:
it sticks better in your head once you fail
im sorry i dont know this i really need points for my maths test
Answer:
It depends on the situation. Most things are better learning from others because others can see what you cant. On the other hand there are some situations were only you can learn from. Take pain as an example. Others can talk about pain as much as they would like but your body dosent know what that feels like unless it feels it on its own and learns from it. An example of learning from others would be smarts such as math, science, history and so forth.
Explanation:
PLEASE HELP ASAP I WILL GIVE BRAINLIEST!
Which statement describes a catalyst?
A) catalysts appear as reactants in a chemical equation.
B) catalysts are completely consumed by the reaction.
C) catalysts provide a lower energy pathway for the reaction.
D) catalysts speed up chemical reaction by increasing surface area.
Answer:
it's D) catalyst speed up chemical reaction by increasing surface area
Explanation:
sorry if I'm wrong
5. How would the food web in Figure 7 change if the numbers of red foxes were
greatly reduced by hunters?
Help meee
Answer:
I cant help you because you didn't provide a picture for the graph
Explanation: