What are covalent bonds
Answer:
A covalent bond, also called a molecular bond, is a chemical bond that involves the sharing of electron pairs between atoms. These electron pairs are known as shared pairs or bonding pairs, and the stable balance of attractive and repulsive forces between atoms, when they share electrons, is known as covalent bonding
can someone explain what radioisotopes are?
Answer:
A radioisotope is a radioactive isotope.
Explanation:
On the Periodic Table, elements 92 and up are radioactive. So that is Uranium and any higher elements. Remember that radioactive elements love to decay and are dangerous.
Isotopes are different forms of an element. For instance, we could have different amount of neutrons in the same element (same number of protons).
We could have an element like He - 4 vs. He - 6, where He - 4 would have 2 neutrons and He - 6 would have 4 neutrons.
So a radioisotope would be an elemental isotope that is radioactive. A good example of this is Uranium.
We have thousands of different isotopes of Uranium, but 2 are well known: Uranium - 235 and Uranium - 238. Both are the same element with the same amount of protons, but both have a different amount of neutrons.
What happens to the tape at the closer markers compared to the markers that are further away?
which natural disaster is most unpredictable?
Answer:
Explanation:
Earthquakes
Earthquakes: Nature's most unpredictable and one of her most devastating natural disasters.
Answer:
Earthquake
Explanation:
Because we have not discovered any high techto predict it, In 2011 a 9.0 earthquake hit the coast of Sendai they had no warning
what kind of rock requires heat and pressure to form?
A-sedimentary rock
b-igneous rock
c-clastic rock
d-metamorphic rock
Answer:
Sedimentary rock can change into metamorphic rock or into igneous rock. ... Igneous rock forms when magma cools and makes crystals. Magma is a hot liquid made of melted minerals. The minerals can form crystals when they cool.
Explanation:
answer: d-metamorphic rock
6. In our modern times, the atom can be subdivided into
A.) protons and electrons, only
B.) protons and neutrons, only
C.) protons, neutrons, and electrons, only
D.) neutrons and electrons, only
Answer:
C.) protons, neutrons, and electrons, only
Explanation:
According to the modern atomic theory, we can distinguish 2 parts in an atom:
The nucleus, where is the majority of the mass of the atom, that is, protons and neutronsThe external shell, where are the electrons.In a neutral atom, there are the same number of protons (positive charges) as electrons (negative charges).
How many atoms are present in 48.60 g ofMg
Answer: Explanation:
There are 6.02 x 10^23 atoms in 1 mol.
what are twoparts of an atom
Why the noble gases are found in small amounts in the earth's atmosphere?
Answer:
They have completely filled outermost shell
Explanation:
The noble gases are the rarest and occur in trace amounts in the atmosphere because they have completely filled outermost and this makes them unreactive with other elements.
Elements become abundant as they combine with other species to form compounds.
Noble gases on the other hand have a high level of stability and do not readily combine with other species.
Some of these gases are :
Helium
Neon
Argon
Krypton
Xenon
Radon
They have very high ionization energy and very low electron affinity and so will not readily react.
HELPP PLEASE
Isotopes have different number of........... *
Protons
Electrons
Neutrons
Protons and Neutrons
Answer:
neutrons. they have the number of protons and electrons
Which statement best describes a physical change?
Changes can occur to certain chemical properties of the substance, but the overall shape of the substance will remain the same.
Changes can occur to certain physical properties of the substance, but the overall shape of the substance will remain the same.
Changes can occur to physical properties of a substance, but the chemical composition of the substance remains the same.
Changes can occur to chemical properties of a substance, but the chemical composition of the substance remains the same.
Answer:
Physical changes can include changing the colour, shape, state of matter, or volume of a substance.
PLEASE HELP FAST !!!
How should measurement of car 2 be taken to accurately measure the distance it travels? Be sure to include where the meter stick should be placed.
the experimental setup, with car 1 is at the top of a ramp and car 2 at the bottom of the ramp
car 1
/ ←top of ramp
/ ←bottom of ramp
car 2
answer
The meter stick should be placed at the starting position of car 2 at the base of the ramp so that it measures the part of car 2 that will end up the furthest away from the base of the ramp.
explanation
i dont know if this is right or not but my teacher gave me a 90 so there is a 50/50 chance its right or wrong
Write the difference between isomerism and allotropy with one example each.
Answer:
hope it helps ..
Explanation:
Allotropes can be defined as different types of compounds made out of the same single element but in different chemical formulas and different arrangements. Isomers can be defined as the chemical compounds that have a similar molecular formula but with different structural formulae. Graphite and Diamond.
This chart shows characteristics of three different types of atoms.
A 3-column table with one row titled valence electrons in three types of atoms. The first column labeled Atom X has entry 6 valence electrons. The second column labeled Atom Y has entry 2 valence electrons. The third column labeled Atom Z has entry 8 valence electrons.
Which statement is best supported by the information in the chart?
Atom X will donate electrons to Atom Y.
Atom X will accept electrons from Atom Y.
Atom Y will accept electrons from Atom Z.
Atom Z will donate electrons to Atom X.
Answer is Atom X will accept electrons from Atom Y.
Atom X will accept electrons from Atom Y.
What is Chart?
The official 511 traveller information service for Maryland is CHART Web. Maryland 511 gives drivers dependable, up-to-date information about traffic, road closures, and weather-related traffic events and conditions.
When driving in Maryland, MD 511 assists drivers in getting to their destination in the safest and most effective way possible.
The term "chart" (sometimes referred to as "graph") refers to a graphical representation of data visualization in which "the data is represented by symbols, such as bars in a bar chart, lines in a line chart, or slices in a pie chart".
Therefore, Atom X will accept electrons from Atom Y.
To learn more about chart, refer to the link:
https://brainly.com/question/15507084
#SPJ7
How many inches are in 4 yards? ( 1 yard = 3 ft and 1 ft = 12 inches)
Answer:
There are 144 inches in 4 yards.
Hope this helps :)
Explanation:
Answer: 144
Explanation:
PLEase help i will give brainliest
Consider the information provided in experiment #3 Figure 2. Three different variables are compared for C3H8 (propane) and H2O (water). The strength of the intermolecular forces are responsible for the behavior of the two compounds.
Identify the intermolecular force for the two compounds.
Which one is stronger?
Explain how the strength of intermolecular forces plays a role in at least two of the properties (volatility, boiling point, or surface tension) for C3H8 (propane) and H2O (water).
Cite evidence from the data to explain your reasoning.
Experiment #3: The student follows study #2 with a comparison of propane (C3H8) and water. Volatility is the tendency for a substance to vaporize and it was found that propane vaporizes quickly while water vaporized slowly. Surface tension is a physical property equal to the amount of force per unit area necessary to expand the surface of a liquid. It is this phenomenon which allows a water strider or lizard to run across the surface of water.
Answer:
what kind of school u doin? lol
which two formulas represent compounds?
A.NaCI
B.HCI
C.H2
D.Ag
Answer: A and B
Explanation: A and b are Sodium chloride and Hydrogen chloride which are both compounds.
Answer: A. NaCI
Explanation: APEX
helppppppppppppppppppppppppppppppppppppppppppppppppp
Answer: it is a
Explanation:
The number of yeast cells in a laboratory culture increases rapidly initially but levels off eventually. The population is modeled by the function а n = f(t) = 1 + be-0.90 where t is measured in hours. At time t = 0 the population is 30 cells and is increasing at a rate of 24 cells/hour. Find the values of a and b. a = b = According to this model, what happens to the yeast population in the long run? O The yeast population will shrink to 0 cells. The yeast population will stabilize at 270 cells. The yeast population will stabilize at 135 cells. The yeast population will stabilize at 8 cells. O The yeast population will grow without bound.
Answer:
Explanation:
[tex]n=f(t)= \frac{a}{(1+be^{-.9t})}[/tex]
At t = 0
30 = [tex]\frac{a}{1 + b }[/tex]
30 + 30 b = a
[tex]\frac{dn}{dt} =f(t)= \frac{-.9abe^{-.9t}}{(1+be^{-.9t})^2}[/tex]
For t = o
[tex]\frac{dn}{dt} =f(t)= \frac{.9ab}{(1+b)^2}[/tex]
given
24 = [tex]\frac{.9ab}{(1+b)^2}[/tex]
24 = [tex]\frac{30\times.9b }{1+b}[/tex]
24 = 27b / 1 + b
24 + 24 b = 27 b
24 = 3 b
b = 8
a = 30 + 30 x 8 = 270
[tex]n=f(t)= \frac{a}{(1+be^{-.9t})}[/tex]
Put t = infinity
n = a = 270
So at infinite time yeast population will stabilise at number 270 .
The Periodic Table of elements is arranged by:
O atomic mass
O number of neutrons
O number of electrons
O atomic number
Option D, atomic number is the correct answer
Answer:
D. Atomic Number
Explanation:
All of the elements in the periodic table are arranged according to their atomic number.
name the following alkynes
Explanation:
1) 3,4-dimethyl hex-1,5-diyne
2) 3,3-diethyl pent-4-yn-1-ene
3) 5-(1'-ethyl-2',3'-dimethyl propane) dec-1,3-diyne
which of the following units of measurement would you use to describe the length of your pencil?
Answer:
cm
Explanation:
cm is the most appropriate unit - metres is too big and mm is too small
Which model represents an element?
Answer: Water. Earth. Fire. Air.
Explanation: the four nations lived together in harmony. Then, everything changed when the Fire Nation attacked. Only the Avatar, master of all four elements, could stop them, but when the world needed him most, he vanished. A hundred years passed and my brother and I discovered the new Avatar, an airbender named Aang. And although his airbending skills are great, he has a lot to learn before he's ready to save anyone. But I believe Aang can save the world."
which in the following best describe carbon
a high density
b. ductile
c. Conductive
d. brittle
Science Graded Assignment Help. Extra points! Due by: 29th of October
A student redid the experiment of mixing room-temperature water and warm
water. This time, she doubled the amount of room temp water. How will the final
temperature be different?
A- It will be higher, because the amount of water in the mixture is greater.
B-It will be lower, because the temperature of the room-temperature water will not increase as much.
C-It will be the same because all parts of the mixture will end up at the same temperature.
D-It will be higher, because all parts of the mixture will end up at the same temperature.
Answer:
B) It will be lower, because the temperature of the room-temperature water will not increase as much.
Explanation: I took the test
Which phrase describes a metamorphic rock?
formed from a volcano
was once buried underground
formed from evaporating water
contains minerals that have not changed
Answer:
C: was once buried underground
Explanation:
Hope this helps!
Answer:
The correct answer you are looking for is B i have got 100% on this test.
Explanation:
hop this helps! └(^o^)┘ ↖(^ω^)↗
Is fire considered matter
Answer:
Fire is a state of matter
Explanation:
Fire is the fourth state if matter called plasma fire is one of thr naturally occuring plasmas we have in existance on earth!
What unit do we measure force in?
Answer: Newton
Explanation:
The SI unit of force is the newton, symbol N. The base units relevant to force are: The metre, unit of length — symbol m. The kilogram, unit of mass — symbol kg.
An aluminium atom has a mass number of 27 and a proton number of 13. How many neutrons does this aluminium atom contain?
Explanation:
14 neutrons
Explanation: The mass number is the total number of protons and neutrons in a nucleus. The atomic number is the number of protons in the nucleus. →27−13=14 neutrons!