Answer:
Surely you must have a Periodic Table beside you....?
a=38
Explanation:
You gots Z=18, the atomic number, where Z is the number of nuclear protons. The number of protons defines the element....and thus we got calcium....
....and with 20 neutrons we got the 38Ca isotope....the which is rather short-lived...
1How do you calculate magnification on a light microscope?
what happens when we mix stone in water observation
Answer:
hope it's help you dear
Explanation:
If one drops a stone into a pond, a very rapid, thin jet of water spouts upwards. ... A cavity forms behind the object during impact on the water surface. This cavity is subsequently compressed by hydrostatic pressure, which leads to the formation of the jet
The mass of an atom of element x is equivalent to the total mass of 7 hydrogen atoms
All living organisms are made of
They are the smallest units of a living.
thing that can perform all life processes.
A. stones
B. cells
C. water drops
D. bricks
write any two effect of gravity
As the human population has grown. Earth's ecosystems and the balance
of natural cycles have been negatively affected. What are some
examples of how the social factors of sustainability (Fig. 1-3) could be
used to help repair environmental damage caused by humans?
40 POINTS I NEEDA ASAP
what is chlorine anyone tell
Answer:
A toxic, green, gaseous chemical element (symbol Cl) with an atomic number of 17.
9. Hydrogen is 99% H, 0.8% ?H, and 0.2% H. Calculate its average atomic mass.
Answer: Technically, this cannot be answered, since none of the H atoms have a mass number assigned. With the assumption noted delow, I calculate 1.012 as the average atomic mass.
Explanation:
My answer is based on assumed masses for the three H isotopes:
1H : 1 AMU
2H: 2 AMU Deuterium
3H: 3AMU Tritium
AMU Rel Abund. Wt. Avg
1H 1 99.00% 0.99
2H 2 0.80% 0.016
3H 3 0.20% 0.006
Sum 1.012
Can someone help me pls, I do not know how to do this. i am trying to help a friend as well
Answer:
Your answer is 5 x 10⁵
I hope it's helps you
Answer:
[tex]thank \: you[/tex]
In this question you should assume that all gases behave ideally.
Hydrogen and iodine react reversibly in the following reaction. The system reaches dynamic
equilibrium.
H2(g) + I2(g) 2HI(g) ∆H=–9.5kJmol–1 Which statement must be true for the Kp of this equilibrium to be constant?
A The partial pressures of H2, I2 and HI are equal.
B The external pressure is constant.
C The forward and reverse reactions have stopped.
D The temperature is constant.
Answer:
B
Explanation:
The number of moles of each reactant is equal, there by pressure has no effect on the chemical system. Pressure is constant
a mixture , the different parts of which vary in composition and properties
Answer:
heterogeneous mixture
Explanation:
(a) A mixture with the same composition and properties throughout is called a homogeneous mixture. (b) A mixture, the different parts of which vary in composition and properties, is called a heterogeneous mixture.
Which of the following is an example of a change from gravitational potential
energy to kinetic energy?
Answer:
The speed of a roller coaster increases as gravity pulls it downhill and is greatest at its lowest point. Viewed in terms of energy, the roller-coaster-Earth system's gravitational potential energy is converted to kinetic energy
Explanation:
a ball held in the air is the example of a change from gravitational potential energy to kinetic energy.
How will a decrease in the concentration of a reactant affect a chemical reaction?
Answer:
When the concentrations of the reactants are raised, the reaction proceeds more quickly. ... When solids and liquids react, increasing the surface area of the solid will increase the reaction rate. A decrease in particle size causes an increase in the .
which is the best interpretation of the two flat portions of the graph
A. These show where kinetic energy is increased
B. These show where temperature is at 0 Celsius
C. These show where thermal energy does not exist
D. These show were changes of state are occurring
Answer:
b
Explanation:
PLEASE SOLVE THIS QUESTION.
VERY MUCH IMPORTANT
Answer:
[tex]thank \: you[/tex]
22. Which of the following is contained only in a eukaryotic cell? A. cell wall
B. nucleus
C. chromosomes
23.Which of the following terms represent the chemical reactions to break down food into simpler compounds in an organism?
A. anabolism
B. catabolism
C. nitrogen cycle
24.What types of molecules are bonded together to form a nucleotide? A. 2 nitrogen bases + 1 sugar
B. 2 sugars + 1 phosphate group
C. 1 nitrogen base + 1 phosphate group + 1 sugar
25.Glucose and oxygen are the two products of photosynthesis A. true
B. false
26.What is the first step in the refining of petroleum? A. cracking
B. drilling
C. distillation
27.When radium-226 (atomic number 88) decays by emitting an alpha particle, it becomes _________.
A. polonium-222 B. polonium-224 C. radon-222
28.The general name for hydrocarbons with at least one triple covalent bond is _________.
A. alkenes B. alkanes C. alkynes
29.What particle is emitted in alpha radiation? A. electron
B. photon
C. helium nucleus
30.Which type of compound is this? CH3CH2CH2CH2OH
A. alcohol B. aldehyde C. ether
31.Why are the molecules of hydrocarbons nonpolar? A. The intermolecular attractions are strong.
B. All the bonds are single covalent bonds.
C. The electron pair is shared almost equally in all the bonds.
32. An amino group and a carboxyl group are joined by a ___________ bond. A. peptide
B. protein
C. amino
33.What type of radiation is likely to occur when the ratio of protons to neutrons is below the band of stability?
A. alpha decay
B. beta decay
C. neutron emission
34.Covalent bonds are between bases in a DNA base-pair. A. true
B. false
35.What is the name of the functional group in the following compound? R—NH2
A. halogen B. amine C. ether
Answer:
22 options A cell wall
23 options A anabolism
24 options B 2sugar + 1phosphate group
what is the density of a 5 mL sample of 1.95g of Gold
Answer:
density=mass/volume
=1.95/5 = 0.39 g(mL)-¹
Which functional group does the molecule below have?
A. Ether
B. Amino
C. Carbonyl
D. Hydroxyl
SUBV
Answer:
Ether is the correct answer
Explanation:
It is based.
All of the following are examples of simple tools except:
A.magnifying glass
B.space telescope
C.pulley
D.lever
Answer:
space telescope I assume
Explanation:
all other tools can be made and used very easily but a telescope took years and years to invent
What are the differences of a physical change and a chemical change?
Answer:
a physical change only changes the look of something whereas a chemical change occurs when one thing has a reaction and it forms a new substance.
draw a diagram to show what happened to the particle, when a liquid cools to a solid?
And do follow if you appreciate it
Describe the differences between models and scientific laws and theories. (
Answer:
Scientific laws and theories have different jobs to do. A scientific law predicts the results of certain initial conditions. ... In simplest terms, a law predicts what happens while a theory proposes why. A theory will never grow up into a law, though the development of one often triggers progress on
Explanation:
Name the reaction & mechanism of the following reactions:
Answer:
double displacement reaction
Answer:
DECOMPOSITION REACTIONDOUBLE DISPLACEMENT REACTIONDISPLACEMENT REACTIONExplanation:
SEE THE IMAGE FOR SOLUTION
HOPE IT HELPS
HAVE A GREAT DAY
Isotopes have
Question 3 options:
A)
a different number of neutrons in their nuclei.
B)
a different number of protons in their nuclei.
C)
a different number of electrons.
D)
different numbers of both protons and neutrons in their nuclei.
Answer:
a different number of neutrons in their nuclei.
Explanation:
Which benzene derivative would be the least reactive in an electrophilic aromatic substitution reaction
Write the molecular formula of ferric oxide and calcium hydroxide by criss-cross method
[tex]\setlength{\unitlength}{1cm}\begin{picture}(0,0)\thicklines\put(0,3){\bf Fe}\put(0,0){\bf -3}\put(4,3){\sf O}\put(4,0){\bf -2}\put(0.2,2.9){\vector(4,-3){3.5}}\put(3.8,2.9){\vector(-4,-3){3.5}}\end{picture}[/tex]
[tex]\\ \sf\longmapsto Fe_2O_3[/tex]
Calcium Hydroxide:-[tex]\setlength{\unitlength}{1cm}\begin{picture}(0,0)\thicklines\put(0,3){\bf Ca}\put(0,0){\bf 2}\put(4,3){\sf OH}\put(4,0){\bf -1}\put(0.2,2.9){\vector(4,-3){3.5}}\put(3.8,2.9){\vector(-4,-3){3.5}}\end{picture}[/tex]
[tex]\\ \sf\longmapsto Ca(OH)_2[/tex]
Note:-
View the answer from web at brainly.com for complete understanding.
Which isotope of iron from the periodic table is most abundant
Answer:
Iron has four naturally-occurring stable isotopes, 54Fe, 56Fe, 57Fe and 58Fe. The relative abundances of the Fe isotopes in nature are approximately 54Fe (5.8%), 56Fe (91.7%), 57Fe (2.2%) and 58Fe (0.3%).
How does the mass of each atom compare to the average atomic mass of the element give in the periodic table?
Explanation:
One is the average weight of an element and the other is the total number of nucleons in the atom's nucleus. Atomic mass is also known as atomic weight. Atomic mass is the weighted average mass of an atom of an element based on the relative natural abundance of that element's isotopes please mark as a brainliest
Things around you. All around you there is matter. The chair you are sitting on, air and
water are all matter. Almost everything that you see is matter. Anything that has mass
and takes up space is called matter.
What do we call something that has mass and takes up space?
Answer:
Hi Lovelys!!
Answers down below!!
Explanation:
There are two answer my me: Matter and Volume
Matter is anything that has mass and takes up space. Mass gives an object the property of weight and inertia (resistance to change in the motion of an object).
Volume simply refers to the space an object takes up. Depending on the physical state of an object, there are a couple ways to measure volume. If we are trying to measure the volume of a box, for instance, we would multiply the length of the box by its height and by its width.
Hope this helps!! =3
Have a wonderful day, evening, or night!! <3
Assuming equimolar quantities of reactants, which compound will react to the greatest extent with boron trifluoride (BF3) in a Lewis acid-base reaction
To solve such this we must know the concept of acid-base reaction. Therefore, NH[tex]_3[/tex] is the compound that will react to the greatest extent with boron trifluoride (BF[tex]_3[/tex]) in a Lewis acid-base reaction.
What is chemical reaction?Chemical reaction is a process in which two or more than two molecules collide in right orientation and energy to form a new chemical compound. The mass of the overall reaction should be conserved. There are so many types of chemical reaction reaction like combination reaction, double displacement reaction.
NH[tex]_3[/tex] is an example of a Lewis Base that will react extensively with BF[tex]_3[/tex] to form the compound NH[tex]_3[/tex] + BF[tex]_3[/tex] → [B (NH[tex]_3[/tex])F[tex]_3[/tex]].
Therefore, NH[tex]_3[/tex] is the compound that will react to the greatest extent with boron trifluoride (BF[tex]_3[/tex]) in a Lewis acid-base reaction.
Learn more about the chemical reactions, here:
brainly.com/question/3461108
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