Answer:
A
Explanation:
What must happen in order for a chemical reaction to be specifically classified as endothermic instead of exothermic is that energy is absorbed in the form of heat.
Chemical reactions can be exothermic or endothermic depending on whether it gives off or absorb energy (in the form of heat).
When energy is given off by a reaction, the temperature of the reaction vessel becomes warmer than the initial temperature before the reaction. Such a reaction is said to be exothermic.
For endothermic reactions, heat energy is absorbed from the surrounding. Thus, the reaction vessel appears colder when compared to the initial temperature before the reaction.
More on exothermic and endothermic reactions can be found here: https://brainly.com/question/4345448
The chemical symbol for silver oxide, an ionic compound used to make button batteries, is made of silver and
oxygen and has a chemical formula of Ag20.
Answer 2 and 1
Answer:
2 Silver Ions
1 Oxygen Ion
Explanation:
Edg2021
The chemical symbol for silver oxide is not Ag₂0. The correct chemical formula for silver oxide is Ag₂O.
Silver oxide (Ag₂O) is an ionic compound composed of silver ions (Ag⁺) and oxide ions (O₂⁻). It is commonly used in button batteries as a cathode material. In this compound, two silver ions combine with one oxide ion to form a stable structure.
The chemical formula Ag₂O indicates that there are two silver ions (Ag⁺) and one oxide ion (O₂⁻) in each formula unit of silver oxide. The subscript 2 after Ag indicates that there are two Ag⁺ ions present, while the absence of a subscript after O indicates that there is one O₂⁻ ion.
Hence, the chemical formulae are discussed above.
Learn more about chemical formulas here:
https://brainly.com/question/32018188
#SPJ 4
The density of lead is 11.342 g/cm 3 . What would be the volume of a 200.0 g sample of this metal?
Answer:
The answer is
17.63 mLExplanation:
The volume of a substance when given the density and mass can be found by using the formula
[tex]volume = \frac{mass}{density} \\ [/tex]
From the question
mass of lead = 200 g
density = 11.342 g/cm³
It's volume is
[tex]volume = \frac{200}{11.342} \\ = 17.6335743...[/tex]
We have the final answer as
17.63 mLHope this helps you
As a star uses up its hydrogen supply, it changes from a main sequence star to a -
A.) dwarf
B.) supernova
C.) black hole
D.) giant
As a star uses up its hydrogen supply, it changes from the main sequence star to a Giant. Thus, the correct option for this question is D.
What is a Star?A star may be defined as a type of huge celestial body that is generally constructed of hydrogen and helium that produce light and heat from the churning nuclear forges inside their cores. They are the luminous bodies that are visible in the sky at night.
A giant is a type of star that has utilized its hydrogen supply in its cores and transformed itself into the thermonuclear fusion of hydrogen in the shell that envelops its surroundings.
This creates an outwards force and stimulates fusion that initiates to increase and hence the star can not able to maintain its equilibrium longer.
Therefore, as a star uses up its hydrogen supply, it changes from the main sequence star to a Giant. Thus, the correct option for this question is D.
To learn more about Red giant, refer to the link:
https://brainly.com/question/27111741
#SPJ6
For the following situations, describe the contact and non contact forces that are involved.
A. A book sitting on a shelf
B. A soccer player kicking a ball; the ball soaring through the air and landing on the ground
C. A hiker in the woods reading her compass to determine which direction to go
D. A child on a sled; first, the child is sitting at the top of the hill, waiting his turn; then, the child pushes off and slides down the hill, eventually coming to a ston
Answer:
D
Explanation:
Bc I got it right
Answer:
For A: the contact I think would be the bookshelf holding it up the non-contact force would be gravity making it so the book would stay where it was put.
For B: the contact force would be the ball being kicked and the non-contact would be the gravity pulling it back to the ground.
For C: A hiker in the woods reading her compass to determine which direction to go The contact would be her holding the compass and moving around the non-contact would be the compass arrow turning every time she moves.
For D: The child on a sled for the contact force would be the person pushing the little kid down the hill the non-contact force would be the gravity that would be keeping the kid going down the hill and gravity stopping the kid at the bottom of the hill.
Explanation:
Have the same assignment and these are the answers I gave. Hope this helps someone!
help please!! will reward brainliest
Answer:
C
Explanation:
just did it and got good luck
Which of the following is NOT a subatomic particle of an atom?
Neutron
Nuclear wall
Proton
Electron
Answer:
B
Explanation:
It is Nuclear wall which is the second one
Which object has the lowest density
beach ball
water
sand
Which of these is a physical property?
A) ability to burn a piece pf paper
B) pure sodium reacts violently with water
C) the boiling point of water is 100°C
D) helium does not tend to react with anything
Answer:
the boiling point of water is 100°C
Explanation:
6.
Which best represents a particle containing 28 protons, 26 electrons, and 34 neutrons?
A Fe2-
B
54
2+
28N;
C%2Fe2-
DSNi2+
Answer:
Ni^2+
Explanation:
The following data were obtained from the question:
Proton = 28
Electron = 26
Neutron = 34
Next, we shall determine the atomic number of the element.
Atomic number of an element is simply defined as the number of protons in the atom of an element.
Thus,
Atomic number = proton number
Proton = 28
Atomic number = proton number = 28
Atomic number = 28
Therefore, the element is Nickel since no two elements have the same atomic number.
Finally, we shall determine the charge on the Nickel atom as follow:
Proton = 28
Electron = 26
Charge on atom =
Charge on atom = Proton – Electron
Charge on atom = 28 – 26
Charge on atom = +2
Therefore, we can represent the Particle as Ni^2+
5. An object is a regular, rectangular, solid with dimensions of 2 cm by 3cm by 2cm. It has a mass of 24 g. find its density.
Answer:
Density, D = 2g/cm^3
Explanation:
Given the following data;
Length = 2cm
Width = 3cm
Height = 2cm
Mass = 24g
Density = ?
Volume of a rectangular solid (V) = Length × Weight × Height
Therefore, V = L× W × H
Substituting the values, we have;
[tex]V = 2 *3 * 2 = 12[/tex]
V = 12cm
Density can be defined as the ratio of mass to volume i.e mass all over volume.
Mathematically, [tex]Density = \frac{Mass}{Volume}[/tex]
[tex]D = \frac{M}{V}[/tex]
Substituting the values, we have;
[tex]D = \frac{24}{12}[/tex]
Density, D = 2g/cm^3
Hence, the density of the rectangular solid is 2g/cm^3.
SHOW YOUR WORK!!!!!!!!!!!!!!!
An experiment performed to determine the density of lead yields a value of 10.95 g/cm3. The accepted value for the density of lead is 11.342 g/cm3. Find the percent error.
Answer:
3.45618%
Explanation:
Percent Error = measured value - accepted value/ accepted value x 100
Measured Value: 10.95
Accepted Value: 11.342
Work:
[tex]\frac{10.95-11.342}{11.342} *100[/tex]
[tex]\frac{-0.392}{11.342} *100[/tex] = -3.45618
You cannot have a negative percentage. Therefore the answer is 3.45618%
Which component of air is given off when silicon dioxide is passed through air during the industrial preparation of air
Answer:
Answer the following questions: What is the composition of air? Answer: Air is composed of nitrogen, oxygen, carbon dioxide, many other gases, water vapour and dust particles. Which gas in the atmosphere is essential for respiration?
Explanation:
Answer:
poop
Explanation:
cus poop
The cell organelles that contains chlorophyll
Answer:
In plants, photosynthesis takes place in chloroplasts, which contain the chlorophyll. Chloroplasts are surrounded by a double membrane and contain a third inner membrane, called the thylakoid membrane, that forms long folds within the organelle.Write the net ionic equation for the acid-base reaction of hydrochloric acid with phosphine. (Include states-of-matter under the given conditions in your answer.)
The net ionic equation for the acid-base reaction of hydrochloric acid with phosphine is PH3(aq) + H⁺(aq) → PH⁺₄ (aq)
What is a Chemical reaction?A chemical reaction shows us how substances interact which brings about changes in the composition of the reactants. Two types of Chemical reactions includes:
the net ionic equation balanced chemical equation.The net ionic equation of a chemical equation tells us only elements and ions directly involved in the chemical reaction.
Now for the reaction of hydrochloric acid, HCl with phosphine, PH3,
First write the aqueous substances in their ionic components
PH3(aq) + HCl(aq)→ PH4Cl(aq)
PH3(aq) + H⁺(aq) +Cl⁻(aq) → PH⁺₄ (aq) + Cl⁻(aq)
Then we remove the ions that do not take part in the reaction, Cl⁻(aq)
So we are left with
PH₃(aq) + H⁺(aq) → PH⁺₄ (aq)
Therefore, the net ionic equation for the reaction of hydrochloric acid with phosphine is PH₃(aq) + H⁺(aq) → PH⁺₄ (aq)
Learn more on Net ionic equation here:https://brainly.com/question/20488944
A hypothesis is based on the analysis of data collected in a controlled
experiment.
True
False
A single paper clip weighs about one gram. So 10 paper clips would weigh?
Which of these would have lowest kinetic energy
Boiling water
Ice water
Refrigerated water
Water at room temperature
Answer:
The answer is ice water, since the particles of a solid have very low kinetic energy.
Explanation:
Answer:
Iced water.
Explanation:
It's a solid. Within a given substance, such as water, particles in the solid state have the least amount of kinetic energy.
As water freezes, it does so because after thermal energy leaves the particles, the average translational+rotational kinetic energy decreases, but the total average kinetic energy does not... and the temperature does not change either.
Which is an example of what should be done in case of a laboratory accident? Wear appropriate lab attire. Read directions completely. Do not try to clean up a spill. Remain in the area.
Answer: C. Do not try to clean up a spill.
Explanation:
What are some ways each person could reduce air pollution and energy consumption? a. adjust the temperature settings - hotter in winter and cooler in summer b. adjust the temperature settings - cooler in winter and hotter in summer c. cut down trees near the house d. replace plumbing fixtures that leak Please select the best answer from the choices provided A B C D
Answer:
b.
adjust the temperature settings - cooler in winter and hotter in summer
Explanation: I took the quiz
Answer:
B. adjust the temperature settings- cooler in winter and hotter in summer
Explanation:
edge 2020
Harvey mixes two liquids. Which observation of the new mixture most likely indicates a precipitate is O A. a cloudy appearance OB. a bubble formation OC. a change in color O D. a change in odor
Answer:
A cloudy appearance!!
Explanation:
Hope it helps, just took a quiz.
Answer:
a cloudy appearance
Explanation:
i have big brain
TIME REMAINING
01:29:12
Which technology has helped improve scientists' ability to gather scientific data about the movement of sea turtles?
O satellite tracking
O thermometers
O probeware
microscopes
the first one satellite tracking
Answer:
I believe the answer is A. Or the 1st dot.
Explanation:
Which statement describes a controlled experiment? A.) It has one group in which the controlled variable is tested, and another in which the manipulated variable is tested. B.) It has one group in which the responding variable is tested, and another in which the responding variable is not tested. C.) It has one group in which the manipulated variable is tested, and another in which the responding variable is tested. D.) It has one group in which the manipulated variable is tested, and another in which the manipulated variable is not tested.
Answer:C.) It has one group in which the manipulated variable is tested, and another in which the responding variable is tested
Explanation: hope this helps
The statement that describes a controlled experiment is that it has one group in which the manipulated variable is tested, and another in which the responding variable is tested (option C).
What is a controlled experiment?A controlled experiment is an experiment where one variable is tested at a time and all other variables are kept constant.
An experiment consists of a manipulated or independent variable, which is the variable changed, and a responding or dependent variable, which is the variable measured.
Therefore, statement that describes a controlled experiment is that it has one group in which the manipulated variable is tested, and another in which the responding variable is tested.
Learn more about experiment at: https://brainly.com/question/11505552
#SPJ5
Silus wants to monitor the temperature of a reaction every 0.5 seconds for 30 minutes. He plans to generate a graph of the temperature values over time and insert the graph into a text document. Which pair of tools would be best for Silus to use?
Answer:
an electronic temperature probe and a computer
Please help me answerrr
Answer:
0.00439 g/mL
Explanation:
plz mark as brainliest if it helps.
Round the number 3456.5 to two significant figures.
Explanation:
35- this is the answer in 2s.f
When rounding a number to two significant figures, we consider the first two most significant digits from the left. In this case, the number is 3456.5. 3456.5 rounded to two significant figures is 3500.
Rounding numbers is a common mathematical process used to simplify or approximate values to a desired level of precision. It involves adjusting a number to a specific decimal place or significant figure.
To round 3456.5 to two significant figures, we look at the first two digits: 34.
The next digit after the second significant digit is 5. Since 5 is greater than or equal to 5, we round up the last significant digit.
Therefore, rounding 3456.5 to two significant figures gives us:
3500
So, 3456.5 rounded to two significant figures is 3500.
For more details regarding rounding numbers, visit:
https://brainly.com/question/29261078
#SPJ6
At the equator, the sun shine heats the air and
causes it to rise. At the north and south pole
there is less direct sun to warm the air, so this
air ______ (blank)
1. rinses
2. stinks
3. rises
4. sinks
Explain what you think a compound is
Answer:
a thing that is composed of two or more separate elements; a mixture.
Explanation:
A
is a changeable factor in an experiment.
O THEORY
O LAW
O HYPOTHESIS
O CONTROL
O VARIABLE
Answer:
Variable is a changebale factor in an experiment.
Explanation:
Answer: O VARIABLE
Explanation:
I need help, pls someone help me!!
HELP ASAP!! A pebble is dropped into a graduated cylinder and the volume rises from 25.0 mL to 31.0 mL. The mass of the pebble is 2.9g. What is the density of the pebble? (g/mL)
Answer:
The density of the pebble is 0.483g/mL (rounded), but it's 0.48333333333333 without rounding. Hope this helped! :)
Explanation:
Volume= 6.0mL Density=Mass/Volume
Mass= 2.9g
D=2.9g/6.0mL
D=0.48333333333333g/mL
or
D≈0.483g/mL