Answer: 12
Explanation:
Which is an example of an exothermic reaction?
A. the rusting of iron
B. dissolving ammonium chloride in water C. photosynthesis
D. baking bread
Answer:
the answer is b
Explanation:
Someone please help will mark as brainliest
Answer:
PET works by using a scanning device (a machine with a large hole at its center) to detect photons (subatomic particles) emitted by a radionuclide in the organ or tissue being examined.
Newer technology combines PET and CT into one scanner, known as PET/CT. PET/CT shows particular promise in the diagnosis and treatment of lung cancer, evaluating epilepsy, Alzheimer's disease and coronary artery disease.
Explanation: Most Brainliest Please
What goes in photosynthesis and what comes out of photosynthesis?
Answer:
Carbon dioxide goes in and oxogen comes out
P.S. Sunlight needed for this process to work
Explanation:
PLS PLS PLS HELP ME I WILL MARK YOU BRAINLYEST PLSSSSS :((
The identity of the element shown in the model above is determined by the number of -
Answer:
The number of protons or electrons in its atomic structure
Explanation:
Elements are substances which constitute the building block of matter. The smallest particles of elements that can ever exist are known as atoms. Atoms of different elements are different in their structure properties. This difference is due to to the number of sub-atomic particles present in the atom of each element.
The three sub-atomicparticles are protons, neutrons and electrons. Protons and neutrons are present in the nucleus of an atom, while the electrons revolve around the nucleus in orbits. The identity of each element is determined by the number of protons present in the atomic nucleus of that element. This is known as the atomic number of that element. For neutral atoms, the proton number is equal to electron number.
For the given element, the electron and proton number are respectively 4, therefore, the atomic number of the element is 4. The element with atomic number 4 is Beryllium.
Balance the following equations:
i. N2 + …..H2 → ….. NH3
ii. P4 + …….O2 → ….P2O5
iii. ……NaF + Br2 →…….NaBr + F2
iv. …..ZnS + …..O2 → …..ZnO + …..SO2
v. Pb(NO3)2 + …..NaCl → ……NaNO3 + PbCl2
(I) [tex]N_{2} + 3H_{2} --> 2NH_{3}[/tex]
(II) [tex]P_{4} + 5O_{2} --> 2P_{2} O_{5}[/tex]
(III) [tex]2NaF + Br_{2} -->2NaBr + F_{2}[/tex]
(IV) [tex]2ZnS + 3O_{2} --> 2ZnO + 2SO_2[/tex]
(V) [tex]Pb(NO_3)_2 + 2NaCl --> 2NaNO_3 + PbCl_2[/tex]
_____________________________________Best Regards,'Borz'Is nuclear energy poised to be part of America’s future?
Answer:
Nuclear energy powers our businesses, homes and military. America’s 95 operating nuclear reactors generate approximately 20% of our nation’s electricity and provide over half of our carbon-free energy. They also create good-paying jobs at power plants and uranium mines. Wyoming produced 87% of America’s domestic uranium supply in 2018.
Today, nuclear energy faces serious hurdles. Regulatory costs and subsidies for renewable energy technologies are forcing America’s nuclear power plants to close at an alarming rate.
Russia and China are subsidizing their government-owned nuclear companies to assert their energy influence around the world. China is searching the globe for uranium reserves and investing heavily in the countries where it’s found. They want to secure more nuclear fuel for themselves and increase their control of the global supply.
Meanwhile, American nuclear power plants have come to rely on cheap Russian imports of uranium to meet their nuclear fuel needs. Right now, roughly 40% of the uranium coming into the United States originates in Russia or its satellite states of Kazakhstan and Uzbekistan. Russian-backed companies are developing fuel that can be placed directly in American reactors.
Explanation:
What is the molar mass of the anhydrous compound? Answer using four significant figures.
36.02 g/mol
120.15 g/mol
156.12 g/mol
Answer:
120.15
Explanation:
ta edg
Answer:
120.15
Explanation:
edg 2021
I need to someone to explain the whole being of Chemistry. I do not understand a single thing, nothing makes sense to me. Literally, I'm going to fail this class because I do NOT understand a single thing taught to me. Maybe it's because I was mistakenly put into Chemistry Pre AP instead of on level but it's so hard and- I just do not get it.
Answer:
Explanation:
In Pre-AP Chemistry, the development of models to explain their macroscopic observations is a primary means through which students develop an understanding of the molecular world.
You will be forced to think and apply concepts to new situations, and even derive your own theories from application. This is excellent preparation for the higher levels of thinking required in college.
Chemistry, the science that deals with the properties, composition, and structure of substances (defined as elements and compounds), the transformations they undergo, and the energy that is released or absorbed during these processes.
Help answer fast please What is an example of homestasis?
A. You drink a bunch of redbull and your heart rate goes up
B. You run, your heart rate goes up, and then your heart rate goes back to its resting rate
C. A person has a fever
D. A person is thirsty but does not drink water
Answer:
c maybe sorry if its wrong
Explanation:
Which choices are layers of the atmosphere?
Select the five correct answers.
Thermosphere
Meteorosphere
Croposphere
Stratosphere
Mesosphere
Danosphere
Exosphere
Troposphere
Answer:
Mesosphere
Stratosphere
Thermosphere
Troposphere
Exosphere
Explanation:
The exosphere refers to the farthest region of the atmosphere that gradually fades into space.
The troposphere is the lowest layer of atmosphere. It is the layer where weather changes occur.
The thermosphere is right above the mesosphere but just below the exosphere. It is the layer where photoionization/photodissociation of molecules occurs thereby creating ions. This largely owes to interaction of molecules in this layer with ultraviolet radiation.
The stratosphere is composed of gases. Prominent among them is ozone which serves as a blanket against the sun's ionizing radiation.
The mesosphere lies above the stratosphere but just below the thermosphere. Temperature decreases steadily with height in the mesosphere.
Question 14
An element's periodic table identity is defined by its number of
А.
neutrons.
B
isotopes.
С C
electrons.
protons
Answer:
c
Explanation:
protons are the atomic number which define an element
What is the mass and volume of the nucleus relative to the size of the atom?
Answer:
The atom with the smallest mass is the hydrogen atom; its mass is about 10-27 kg. The masses of other atoms go up to about 200 times this. The nucleus of an atom is about 10-15 m in size; this means it is about 10-5 (or 1/100,000) of the size of the whole atom.
What is true of both galvanic and electrolytic cells?
A. Reduction happens at the cathode.
B. They are spontaneous. .
C. They are nonspontaneous.
D. Oxidation happens at the cathode.
Answer:
reduction happens at the cathode
Explanation:
Just took the test.
Reduction happens at the cathode. Hence, option A is correct.
What is an electrolytic cell?An electrolytic cell converts electrical energy into chemical energy or vice versa.
Oxidation-reduction reactions are balanced by two half overall chemical equations into an oxidation equation and a reduction equation.
Hence, reduction happens at the cathode in both galvanic and electrolytic cells.
Learn more about electrolytic cells here:
brainly.com/question/4030224
#SPJ2
What do radio waves and microwaves have in common?
O Both have shorter wavelengths than visible light
O Both are at the side of the spectrum that has the highest frequency
O Both have lower frequencies than visible light
O Both have radiant energy than visible light.
Answer:
The last one
Explanation:
What is the volume of 50.0 g of table sugar if the density of the sugar is 1.59 gcm3 ?
Answer:
31.45 cm³Explanation:
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 we have
[tex]volume = \frac{50}{1.59} \\ = 31.446540...[/tex]
We have the final answer as
31.45 cm³Hope this helps you
A glass of fresh milk with 4% fat is an example of *
4 points
a heterogeneous mixture.
an element.
a homogeneous mixture.
a compound.
Answer:
heterogeneous
Explanation:
composition is not uniform through out
calculate the energy required to vaporize a chunk of ice at -25°C with the mass of 12.5kg
Consider the following reaction: 3Fe(s) + 4H₂O(g) ➞ Fe₃O₄(s) + 4H₂(g). To answer the following question: "How many moles of hot water vapor (steam) must react to produce 275 g of Fe₃O₄?" How many steps will it take to get the answer? *
4 points
1
2
3
4
What will a medium mass star become at the very end of its life cycle
true or false, during a change of state, the thermal energy gained or lost by a material changes the kinetic energy of its particles
Answer:
true..... not false okkkkk
what are the names of these compounds??
CCI4
K2O
Answer:
CCI4 Carbon tetrachloride
K2O Potassium oxide
Explanation:
The diagram below shows a longitudinal wave at one instant in its motion. Each oval represents a particle acted on by the energy of the wave as it moves from left to right.
Which line on the diagram indicates a region of rarefaction?
Answer: It is the middle one on the bottom
Explanation:
trust me i just did this question
A solution is made by dissolving 0.0503 kg of biphenyl (C12H10) in
350.0 mL of benzene (C6H6).
What would be the osmotic pressure (in atm) of this solution at 40.0
°C? (The density of benzene is 0.877 g/mL.)
Answer:
Letter A po
Explanation:
yanffdddddd
Aqueous solutions of sodium carbonate and magnesium chlorate are mixed
Explanation:
You're mixing magnesium nitrate, Mg(NO3)2 , and sodium carbonate, Na2CO3 , two soluble ionic compounds that dissociate completely in aqueous solution to form cations and anions.
I NEED HELPPPPPP ASAP
Answer:
1. Reactants collect in chloroplasts
2. A chemical reaction occurs
3. Products result as food and water
please help me solve step by step!!
A motorcycle and its rider have a combined mass of 1250 kg. They travel inside
a vertical loop with a radius of 7.13 m. At the lowest point, the speed is 22.7 m/s. How much force does the track exert on the motorcycle, at this lowest
point, to keep the rider in the loop?
Which is greater 50 degree celcius or 50 degree fahrenheit?with solution plz.....
Answer: 50 degrees Celsius is hotter than 50 degrees F. 50 degrees Celsius is half way between freezing and boiling
Fill in the blanks. A person would weight more on Neptune than on planet blank
because
blank
A person would weigh more on Neptune than on planet earth because the gravitational field strength is stronger on Neptune.
A person would weight more on Neptune than on planet earth because the gravitational force in neptune is more.
What is gravitational force?Gravitational forces is a kind of attraction force which is present between two objects of masses.
Gravitational force on the neptune planet is more as compared to the gravitational force on the earth. So the mass of any object present in the neptune is more than the earth.
Hence a person would weight more on Neptune than on planet earth because gravitatinal force in neptune is more.
To know more about gravitational force, visit the below link:
https://brainly.com/question/19050897
#SPJ2
Observe: Look at the red lithium atom and the blue oxygen atom. Recall that most atoms are stable when their outermost ring has eight electrons. (Some atoms, such as lithium and beryllium, are stable when their outermost ring has two electrons.)
How many electrons will the lithium atom give up to become stable?
1. eight
2. seven
3. two
4. one
Answer:
4. one
Explanation:
