Answer:
8, they have a full valence shell
Explanation:
What can you infer if the fossil of a marine organism is found in an area that is now dry land?
Answer:
Fossils also help us to infer why dinosaurs and other organisms became extinct. Fossils tell us that there was a mass extinction at the time of the dinosaurs. They died out about 65 million years ago, along with more than half of all the other animal and plant species. ... Without plants, dinosaurs could not survive.
Explanation:
hope it will help you have a great day bye and Mark brainlist if the answer is correct
[tex]kai6417[/tex]
#carry on learning
28.5g of iron shot is added to a graduated cylinder containing 45.50 mL of water. The water level rises to the 49.10 mL mark, from this information, calculate the density of iron.
Explanation:
this is a very easy question, you just need to know the formula of density, the mass and volume.
you're given the mass of the iron which is 28.5g and when it is submerged into a cylinder containing 45.50 ml, it rises to 49.10 ml. the volume of water displaced gives you the volume of the iron. thus,
V² - V¹ = 49.10 ml - 45.50 ml
V of iron = 3.6 ml
now that you know both the mass and volume, you can work out the question.
density (ρ) = mass / volume
ρ = m/v
ρ = 28.5 g / 3.6 ml
ρ = 7.916666...
ρ = 7.92 g/ml (3 sf)
hope this helps you!
- s.
Is this correct?? please help
Yes it is but I have to check so wait
16. For the reaction below, A) calculate the total bond energy, using the equation: Reactant energy - product energy = total energy.
Answer:
C=C divided by the co effiecient 11 would make the denominator of the photosynthesis equal 11 over 5 making this problem a polywhirl which wouldnt matter in the sense of the quake in energy change so thus making the answer 728 kJ/mol
Explanation: back in my day
A sample of rest of the following composition 51.85 g of iron 22.22 g of oxygen 16.67 g of water
Answer:
To calculate the percent composition, we need to know the masses of C, H, and O in a known mass of C9H8O4. It is convenient to consider 1 mol of C9H8O4 and use its molar mass (180.159 g/mole, determined from the chemical formula) to calculate the percentages of each of its elements:
%
C
9
mol C
×
molar mass C
molar mass
C
9
H
18
O
4
×
100
=
9
×
12.01
g/mol
180.159
g/mol
×
100
=
108.09
g/mol
180.159
g/mol
×
100
%
C
60.00
%
C
Would a saturated fatty acid hold more potential energy or less potential energy than an unsaturated fatty acid
Answer:
Yes, it is a fact that saturated fats contain more gross energy due to higher H+ concentration. However, unsaturated fats are more digestible and have higher absorption rate, and therefore the metabolizable energy that unsaturated fats provide is higher than that provided by saturated fats.
Explanation:
Assume that there is a puddle that contains 12.0 kg of water and it froze outside since it is -1°C. The
custodian threw 6.00kg of salt (NaCl) onto the puddle and we assume that all the water melted and the
sodium chloride completely dissolved into the water. What temperature would it need to be to re-freeze
that solution?
The temperature that must be to freeze the solution would be -21.1 ° C.
How to calculate the freezing temperature of this solution?To calculate the freezing temperature we must take into account the following information.
Solution with a salt concentration of 10% is frozen at -6°CSolution with a salt concentration of 20% is frozen at -16°CSolution with a higher concentration is frozen at -21.1°CAccording to the above, it can be inferred that the puddle has a 50% concentration of salt because they had 12 kg of water and 6 kg of salt.
So the lowest freezing temperature would be 21.1°C because the puddle is 50% concentrated.
Note: This question is incomplete because there is some missing information. Here is the missing information:
A 10% salt solution freezes at about 20°F (-6°C), and a 20% solution freezes at 2°F (-16°C).The lowest freezing point obtainable for salt solutions is −21.1 °CLearn more about freezing in: https://brainly.com/question/14131507
What type of process occurs when heat flows out of a system?
endothermic: Heat is absorbed by the system from the surroundings. exothermic: Heat is released by the system into the surroundings.
what is the best way to memorize the periodic table
Answer:
- breaking it down into sections
-learn the element song
-use colors to learn the element groups
Explanation:
what also may help which is time-consuming is writing it out over and over if not I would prefer to learn the song it may seem childish a little but it will help in the long run.
Answer:
I personally have a method for learning stuff like this.
Try going one at a time, and ever once in awhile. Like memorize the first element, then the one next to it [in whichever order you please]
Ex: memorizing 1-10
1.. 1,2.. 1,2,3.. 1,2,3,4..
And then repeat that row until you can recite it almost without hesitation, then move onto another line.
This works for both placement memorization and element name.
suggest why it might be difficult and dangerous to test sodium for electrical conductivity?
Answer:
It might cause fire or extreme smoke.
Explanation:
How many protons, neutrons, and electrons does cobalt-60 have? Is this a "normal" isotope of cobalt and how do you know?
Use the equation below to answer the following questions:
2 C4H10 + 13 O2 → 8 CO2 + 10 H2O
A) How many moles of O2, are needed to react with 25.9g of C4H10?
B) If 22.2 g of CO2 is produced, what mass of water is also produced?
C) How many moles of oxygen gas are needed to produce 0.30 moles of carbon dioxide?
Answer:
A (2.475 mol O2). B (11.35 g) C. (.4875 mol O2)
Explanation:
A.
convert 25.9 g C4H10 (68g/mol) to mol. --> .3808 mol
then use mole ratios from equation
.3808 mol C4H10 x (13 mol O2 / 2 mol C4H10). ---> 2.475 mol O2
B.
convert 22.2 g CO2 (44g/mol) to mol. ---> .5045 mol
.5045 mol CO2 x (10 mol H2O / 8 mol CO2) ----> .6306 mol H2O
convert .6306 mol to g ----> 11.35 g
C.
.3 mol CO2 x (13 mol O2 / 8 mol CO2) ---> .4875 mol O2
Which element will chemically combine with fluorine to combine salt?
Answer:
When an atom of sodium and an atom of fluorine combine to form the salt, sodium fluoride, an ionic bond, is formed.
Explanation:
What does this piece of evidence best support? the collision theory the Maxwell-Boltzmann distribution the effect of pressure on reaction rates the effect of temperature on reaction rates.
Particles are the smallest units of any state of matter that moves in a medium due to various factors. The particle movement best supports the collision theory.
What is collision theory?In a reactant, the particles move and collide with each other resulting in some amount of change and the collision between the atoms and the molecules are necessary for a chemical reaction to occur.
This theory of collision is used for the prediction of the rate of the reaction to occur and the chemical changes occurring in a gas or the reactant. This aids in understanding the rate of reaction occurring in a system.
The collision of the particles is proportional and related to the rate of the reaction. The amount of the concentration and their collision affects the rate at which the chemical change will occur.
Therefore, option A. the collision theory is supported here.
Learn more about collision theory here:
https://brainly.com/question/14566831
A tank of gas has partial pressures of nitrogen and oxygen equal to 1. 61 atm and 4. 34 atm, respectively. What is the total pressure of the tank?.
The partial pressure is the pressure exerted by individual gas in the mixture. The total pressure of the tank is 5.95 atm.
What is Dalton's law of vapor pressure?According to the Dalton's law of vapor pressure, the total pressure of the gas is the sum of the partial pressure of individual gas in the mixture.
The tank has mixture of nitrogen and oxygen gas. The partial pressure of nitrogen gas ([tex]P_{N_2}[/tex]) is 1.61 atm, and the partial pressure of oxygen ([tex]P_{O_2}[/tex]) is 4.34 atm.
The total pressure of tank ([tex]P[/tex]) according to Dalton's law can be given as:
[tex]P=P_{N_2}+P_{O_2}\\P=1.61+4.34\;\rm atm\\\textit P=5.95\;atm[/tex]
The total pressure of the tank is 5.95 atm.
Learn more about partial pressure, here:
https://brainly.com/question/14623719
If an external stimulus is acting to increase the pH of blood (making the blood more alkaline), what chemical or ion is being generated in the bloodstream and needs to be neutralized
When the blood pH increase from the normal, carbonic acid is the chemical which neutralize it.
Chemical that neutralize blood with high pHWe know that acid neutralizes base whereas base neutralize acid. In the blood, bicarbonate ion is responsible to neutralize acid.
While on the other hand, bases in the blood increase the pH which are neutralized by carbonic acid (H2CO3) so we can conclude that carbonic acid neutralizes increase pH of the blood.
Learn more about pH here: https://brainly.com/question/172153
Energy is transferred from the sun to Earth mainly by
C. compressional waves
A. sound waves
D. electromagnetic waves
B. air currents
Answer:
electromagnetic waves
Explanation:
Radiation is the transfer of heat energy through space. Most of them are sent through electromagnetic waves.
How is genetic variation introduced into a population? Choose all that apply.
I NEED ANSWER ASAP
Answer: Genetic variation can be caused by mutation (which can create entirely new alleles in a population), random mating, random fertilization, and recombination between homologous chromosomes during meiosis (which reshuffles alleles within an organism's offspring).
Explanation: hope this helps
Gene variants, sometimes known as mutations, can cause genetic differences, or a normal process in which genetic information is rearranged as a cell prepares to divide can also cause genetic variations. Different phenotypes can be introduced into an organism by genetic changes that change gene activity or protein function.
What is mutation ?An alteration in the nucleic acid sequence of an organism's, virus's, or extrachromosomal DNA is referred to as a mutation. DNA or RNA can be found in the viral genome.
Mutation, chance mating, chance fertilization, and recombination between homologous chromosomes during meiosis can all result in genetic variation. Genetic variety is primarily caused by mutations, although it is also influenced by other processes, including genetic drift.
A single nucleotide base can change in a genetic mutation known as a point mutation. DNA mutation, gene flow, and sexual reproduction are the main causes of genetic variation.
Thus,Mutation and genetic recombination are two of the many processes that cause genetic variation.
To learn more about mutation, follow the link;
https://brainly.com/question/13923224
#SPJ2
Which period is older than the Triassic period? Cambrian Cretaceous Jurassic Paleogene.
The Triassic period is one of the geological periods and is the shortest of the Mesozoic era. Cambrian is the older era than the Triassic period.
What is Cambrian and triassic period?The Triassic period existed 250 -200 million years ago and started after the vastest and most extreme devastation ever. It is the 1st period of the Mesozoic and is known for the movement of the Dinosaurs on the land, flying pterosaurs and swimming plesiosaurs and ichthyosaurs.
The Cambrian is the period of the Paleozoic era and is the most important period because of the appearance of many animals. In this period, the temperature raised on the planet and the ice sheets melted at a very dangerous rate leading to mass devastation.
Therefore, option A. Cambrian is older than the Triassic period.
Learn more about Cambrian and Triassic periods here:
https://brainly.com/question/11417834
Answer:
A: Cambrian!
Explanation:
got it right on ed :)
35 points!!! please help me
Answer:
give answer of following questions and get 35 points.
Which of these are products of photosynthesis?
Question 2 options:
oxygen and chlorophyll
carbon dioxide and water
oxygen and sugar
oxygen and carbon dioxide
Answer:
carbon dioxide and water
Explanation:
The process by which plants make their food with the help of water, carbon dioxide, sunlight and convert it into sugar and provides energy to the plant.
Hope it helps you.
Stay safe, stay healthy and blessed.
Have a great day !
Thank you
How many bonds are broken in the combustion of one methane molecule?.
According to the number of bonds present in a methane molecule, in the combustion of one methane molecule, four C-H covalent bonds are broken.
How many bonds are broken in a methane molecule?A methane molecule is composed of four atoms of hydrogen and one atom carbon.
The formula of a methane molecule is CH4.
The bonds present in methane molecule are four C-H covalent bonds.
Therefore, in the combustion of one methane molecule, four C-H covalent bonds are broken.
Learn more about about methane at: https://brainly.com/question/25419929
A gas has a volume of 250 mL at 0.29 atm. What will its volume be if the pressure is changed to 0.70
atm?
Explanation:
I answered your question in the submitted photo
One hundred points to whoever answers first and brainleist.
Is carbon ever lost in the cycle? Is it constantly conserved 100% of the time? What about mass and energy? Are mass and energy ever lost in a continuous cycle?
Answer:
Carbon is never really lost in the cycle. Carbon is constantly added and removed from the carbon cycle. Example..... Carbon dioxide is removed from the air by photosynthesis and dissolving in the ocean buttttt at the same time it is added to the atmosphere by respiration and combustion.
As for the mass and energy....the Law of Conservation of Matter states that matter cannot be created or destroyed.
Answer:
no its not ever lost
Explanation:
7. Justify why these ions do not exist under normal conditions.
(a) K2+
(b) 0-
K^+ can not exists because electrons are removed from an inner shell. The ion O^- can not exist because it will have an incomplete octet.
Stability of ionsIons are species that contain a positive or a negative charge. When we consider the electron configuration of ions, we can deduce the stability of the ion.
Let us consider the electron configuration of K^2+ which is 1s2 2s2 2p6 3s2 3p5 which means that the second electron is to be removed from an inner shell which implies greater energy expenditure hence it does not exist.
In the case of O^-, involves the formation of an ion with an incomplete octet which is not possible.
Learn more about ions: https://brainly.com/question/1782326
Which two statements describe how igneous rock is formed?
O A. Existing rock changes into new kinds of rock due to heat and
pressure.
OB. Solid rock melts to form magma and then solidifies as it cools.
O C. Liquid rock hardens into solid rock as it cools underground.
I D. Solid rock breaks down into fragments that become part of new
rock.
Answer:
B and C
Explanation:
I just took the test
Answer:
B. and C.
Explanation:
which of the following is a pure compound A. ethanol B. petrol C. steel D. tap water
Answer:
D. tap water
keep on learning!
Answer: ethanol
Explanation: as it is a pure compound and can sometimes be a mixture while all the rest are mixtures.
How many moles of atoms are in 454 g of lead?
Answer:
207.2
Explanation:
One mole of lead weighs 207.2 g. Thus, number of moles in 454 g of lead is determined by dividing the given mass by atomic mass that is ., 2.19 moles.
What is lead ?Lead is 82nd element in periodic table. It is in 14th group. Lead is classified among non-metals but it is a heavy metal in nature. Lead have many naturally stable isotopes of which two are radioactive.
A substance containing 6.02 × 10²³ atoms is called its one mole. This number is called Avogadro number. Hence, one mole of every elements contains Avogadro number of atoms. The mass of one mole of an element is called its atomic mass.
Atomic mass of lead (Pb) = 207. 2 g/mol
thus, number of moles in 454 g of Pb = given mass/atomic mass
no.of moles = 454 /207.2 = 2.19 moles.
Therefore, the number of moles of Pb in 454 g is 2.19.
Find more on lead:
https://brainly.com/question/11999159
#SPJ2
A compound that donates hydrogen ions to a solution is.
Answer:
an acid
Explanation:
An acid is a substance that donates hydrogen ions.
which continent has the greatest totals population
Answer:
Asia
Explanation: