Answer:
70
Explanation:
There are 5 significant figures in the problem. Since it has a decimal point, we start on the left hand side and work our way to the right. You would end up at 69, but then you have to round up since the next number is a 7, which is greater than or equal to 5.
What must occur in order for a chemical reaction to be specifically classified as endothermic instead of
exothermic?
Atoms are rearranged.
Chemical bonds are formed.
Energy is released in the form of heat.
Energy is absorbed in the form of heat.
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.
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Which one would it be?
Answer:
it would be C! 0.0520 Km
Mass is usually measured in grams and
Which structure represents the cytosol within the cell
Answer:
In the eukaryotic cell, the cytosol is surrounded by the cell membrane and is part of the cytoplasm, which also comprises the mitochondria, plastids, and other organelles (but not their internal fluids and structures); the cell nucleus is separate. The cytosol is thus a liquid matrix around the organelles.
Answer:
C
Explanation:
answer on khan
Which of the following properties of an unknown substance would allow it to be classified as a pure substance ?
A- can be dissolved into a solution
B- has a definite composition throughout
C- combines easily with other substances
D- is made of a single element or compound
D because that’s the only one that makes sense
Pure substances typically only include one type of atom or molecule and are homogeneous in nature. The majority of these chemicals have a consistent or homogeneous makeup. Thus, option C is correct.
What is pure substance?Elements are pure compounds that cannot be chemically broken down into less complex ones. Iron, gold, sulfur, oxygen, and oxygen are some well-known elements.
Because it cannot be converted into a more basic substance, an element is an example of a pure substance. Examples of pure substances include water, neon, and sodium chloride (NaCl) (table salt).
One element or a few related compounds make up pure substances. A kind of matter with a predictable chemical composition and physical properties is referred to as a chemical substance.
Homogeneous mixes are made up of two or more components or compounds that cannot be seen separately from one another.
Therefore, a single element or compound show properties of pure substance.
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Which pair of elements in the diagram is most likely to form a covalent bond?
Answer:
This question is incomplete
Explanation:
This question is incomplete. A covalent bond is a bond that involves the sharing of valence electrons (shared pair) by two atoms of the same/different elements/compounds. The electrons (valence) that are involved in covalent bonding are not the ones in pairs (lone pairs) on the outermost shell of the atom. For example, the single electron on a hydrogen atom is shared with another hydrogen to form hydrogen gas (H₂).
Another example is when the two individual/unpaired electrons on the outermost shell of an oxygen atom binds with two other unpaired electrons on the outermost shell of another oxygen atom.
Another example is when two different electrons from two hydrogen atom binds singly with the two unpaired electrons on the outermost shell of an oxygen atom to form water.
The diagram in the attachment provides illustration on the examples given.
CONCLUS Your conclusion will include a summary of the lab results and an interpretalion of the results. Please answer al questions in complele sentences using your own words Using two to three sentences, summarize what you investigated and observed in this lab What I observed in this lab was what materials to use for different things. I also learned how to make things sturdier. 2 What building malerial did you use to build your house? My house is made.autof brick and/or clay brick and wood. 3 Did your results support or fail to support your hypotheses? Type Here IN 4 What were the densities of the malerials you chose for the was ond floor for the home in Thy Worlar Type Here Why do you think a building material's density is important when building homes or architectural structures? Type Here Why wouldn't you choose wood or aluminium for the lalches on your house? Type Here Help Improve Office Notes
Answer:
Here’s the answer
Explanation:
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
How do scientists determine the number of neutrons in an isotope of an atom? O They find the number of protons. 0 They add the number of electrons and protons. They divide the atomic mass by two. They subtract the atomic number from the atomic mass.
Answer:
The three naturally-occurring isotopes of hydrogen. The fact that each isotope has one proton makes them all variants of hydrogen: the identity of the isotope is given by the number of protons and neutrons. From left to right, the isotopes are protium (1H) with zero neutrons, deuterium (2H) with one neutron, and tritium (3H) with two neutrons.
The term isotope is formed from the Greek roots isos (ἴσος "equal") and topos (τόπος "place"), meaning "the same place"; thus, the meaning behind the name is that different isotopes of a single element occupy the same position on the periodic table.[2] It was coined by a Scottish doctor and writer Margaret Todd in 1913 in a suggestion to chemist Frederick Soddy.
The number of protons within the atom's nucleus is called atomic number and is equal to the number of electrons in the neutral (non-ionized) atom. Each atomic number identifies a specific element, but not the isotope; an atom of a given element may have a wide range in its number of neutrons. The number of nucleons (both protons and neutrons) in the nucleus is the atom's mass number, and each isotope of a given element has a different mass number.
For example, carbon-12, carbon-13, and carbon-14 are three isotopes of the element carbon with mass numbers 12, 13, and 14, respectively. The atomic number of carbon is 6, which means that every carbon atom has 6 protons, so that the neutron numbers of these isotopes are 6, 7, and 8 respectively.
what is strong interaction in atoms
Answer:
Alternative Titles: nuclear force, strong interaction, strong nuclear force. Strong force, a fundamental interaction of nature that acts between subatomic particles of matter. The strong force binds quarks together in clusters to make more-familiar subatomic particles, such as protons and neutrons.
What's the largest planet on Earth?
Answer:
Asia
Explanation:
Answer:
Asia.
Explanation:
An atomic number stands for the number of _____. neutrons in the nucleus of an atom protons in the nucleus of an atom valence electrons in an atom protons plus neutrons in the nucleus of an atom
Answer:
atoms or electrons
Explanation:
but l guess electrons is the best answer
Which statement describes a chemical property that many elements might share?
A. bonds easily with oxygen in the air
B. boils between 90°C and 100°C
C. shines when polished
D. floats in water
ANSWER:
I think its B.
please help me with answering this question :( asap!!
Answer:
32. CnH2n+2
33. Ester
34. Water and corbondioxide.
35. dibromoethane
The most common isotope of chromium is 52Cr. How many neutrons does an atom of 52Cr have?
a. 24
b. 28
c. 52
d. 80
Cathy is reading a science article about exercise. She learns that exercise
causes a person to breathe faster. The next part of the article has the title
"Heart Rate." In that part of the article, Cathy is sure she'll read about how
exercise causes the heart to beat faster. What active reading strategy is
Cathy using?
A. Monitoring and applying fix-up strategies
O B. Summarizing
O C. Making predictions
D. Making mental images
Flammable materials, like alcohol, should never be dispensed or used near Group of answer choices an open door. a sink. another student. an open flame.
Answer:
An open flame. Hope this helped! :)
Igneous rock can be changed into which type of rock through the application of heat and pressure?
A. metamorphic rock
B. foliated igneous rock
C. clastic sedimentary rock
D.non-foliated igneous rock
(Pls help me)
Answer:
A) metamorphic rock
Explanation:
Granite is an igneous rock that forms when magma cools slowly underground. When granite is exposed to heat and pressure it changes into a metamorphic rock called gneiss
Which property is a physical property?
A:malleable
B:becomes moldy quickly
C:easy to digest
D:does not burn
Answer:
The answer is B. Becomes moldy quickly.
Explanation:
This is the most logical answer out of all of them an I took the test.
What’s the phase change to solid to gas
a glass of.water contains 500g of liquid and 500 ml of liquid what is the density
Answer:
Explanation:
density=mass/volume
density=500/500
=1g/ml
A student places 1.38g of unknown metal at 99.6C into 60.50g of water at 22.1C. The entire system reaches a uniform temperature at 31.6C. Calculate the specific heat of the metal
Explanation:
Heat energy lost by metal = Heat energy gained by water.
(0.00138kg) * c * (99.6-31.6) = (0.006050kg) * 4.148 * (31.6-22.1)
c = 2.541J/kg°C
Which of these features of Earth's crust are caused by the shifting of tectonic plates?
A
mid-ocean ridges
B
desert sand dunes
С
arctic glaciers
D
continental shelves
To solve this we must be knowing each and every concept related to tectonic plates. Therefore, the correct option is option A among all the given options.
What is tectonic plates?The lithosphere, which includes the crust and topmost mantle, is divided into portions by tectonic plates. Numerous dangers, including volcanic eruptions, earthquakes, and tsunamis, are caused by the relative movement of tectonic plates.
Because of the makeup of the rocks inside the plates, tectonic plates can float on the mantle. This reduces their density relative to the mantle. Granite rock, which contains quartz, feldspar, as well as other relatively light materials mostly comprised of silicon and aluminum, makes up the continental crust. Mid-ocean ridges, earth's crust are caused by the shifting of tectonic plates.
Therefore, the correct option is option A.
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yo someone please help meee The density of silver is 10.5 g/cm3. What is the mass (in kilograms) of a cube of silver that measures 0.69 m on each side?
Mass of the cube of silver is 3,449.34 kg
First find the volume of the cube in centimeters because the density is in centimeters:
0.69 * 100 = 69 centimeters
Volume = Side * Side * Side
= 0.69 x 0.69 x 0.69
= 328,509 cm³
The density of a material is calculated by the formula:
= Mass / Volume
As you have the density already and the volume, you can get the mass:
10.5 = Mass / 328,509
Mass = 10.5 * 328,509
= 3,449,344.50 grams
A kilogram is 1,000 grams so the mass in kg is:
= 3,449,344.50 / 1,000
= 3,449.3445 kilograms
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To calculate the charge of an atom you must
Answer:
The charge of an element is equal to the number of protons minus the number of electrons. The number of protons is equal to the atomic number of the element given in the periodic table. The number of electrons is equal to the atomic number minus the charge of the atom.
Explanation:
you have a lead ball with a mass of 420 g. the density of lead is 10.5 g/cm³. what is the volume of the ball
Answer:
The answer is
40.0 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 = 420 g
density = 10.5 g/cm³
The volume is
[tex]volume = \frac{420}{10.5} \\ [/tex]
We have the final answer as
40.0 mLHope this helps you
A proton and a neutron are each close to a positive nucleus.
How does the charge on the nucleus affect the proton and the neutron, if at all?
A The neutron is attracted; the proton is repelled.
B The neutron is not affected; the proton is repelled.
C The proton is attracted; the neutron is repelled.
D The proton is not
Answer : The same charges will repel, since all protons are positively charged they will all repel so protons will repel. Neutrons don’t carry a charge so they can’t be repelled
So the answer is B: the neutron is not affected; the proton is repelled
Answer:
B
because the proton is positively charged and like charges repel, the neutron doesn't have a charge so nothing happens to it
Wait you wrote the answer in the question??
The way charge on the nucleus affect the proton and the neutron, if at all is the neutron is not affected; the proton is repelled.
What is electric charge?Electric charge refer to the physical property of a particle which direct or influence how it react to electric or magnetic force acting on it.
Therefore, The way charge on the nucleus affect the proton and the neutron, if at all is the neutron is not affected; the proton is repelled.
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What is the temperature 51°C expressed in kelvins?
Answer:
The answer is
324 KExplanation:
To express a given temperature in degree Celsius to Kelvin simplify add 273 to the given value
That's
K = 273 + °Cwhere
K = Kelvin
°C = value in degree Celsius
From the question the value to be converted is 51°C
It's equivalent in Kelvin is
K = 273 + 51
We the final answer as
324 KHope this helps you
Rank the nonmetals in each set from most reactive (1) to least reactive (3). bromine chlorine iodine
Answer:
1. Chlorine 2. Bromine 3. Iodine
Explanation:
Answer:
Bromine: 2 Chlorine: 1 Iodine: 3
Explanation:
What is the name of the binary molecule H2O2
Explanation:
H2O2: hydrogen peroxide.
hope it will help u ✌️