Answer:
Tác giả văn bản ' Mẹ tôi ' : Edmondo De Amicis ( 1846-1908 ) là nhà văn người Ý ( I-ta-li-a )
Sequence Examine the periodic table.
Which four pairs of elements would be
reversed in order if the elements were
listed by increasing atomic mass instead of
increasing atomic number?
Answer:
Notice that tellurium is listed before iodine even though its atomic mass is higher. Mendeleev reversed the order because he knew that the properties of iodine were much more similar to those of fluorine (F), chlorine (Cl), and bromine (Br) than they were to oxygen (O), sulfur (S), and selenium (Se).
The tellurium is listed before iodine even though its atomic mass is higher. Mendeleev reversed the order because he knew that the properties of iodine were much more similar to those of fluorine (F), chlorine (Cl), and bromine (Br) than they were to oxygen (O), sulfur (S), and selenium (Se).
What things are in the periodic table?The periodic table is a tabular Form of the chemical elements classified by atomic number, from the element with the least atomic number, hydrogen, to the element with the most atomic number.
The atomic number is the number of protons in the nucleus of an atom.
Thus, The tellurium is listed before iodine even though its atomic mass is higher. Mendeleev reversed the order because of its properties.
To learn more about periodic table click here:
https://brainly.com/question/11155928
#SPJ2
*
Identify the element found in the f-block.
Cm
K
W
Br
Ag
Explain why the sodium ions and chloride are attracted to each other.
Answer: The reason a bond is formed between chloride ions and sodium ions is because they have opposite charges. TRUE: the opposite charges attract them together, and this force of attraction is the ionic bond.
Explanation:
6. What can you do to reduce the environmental and political
impact of obtaining rare earth elements from the ground? |
Answer:
u can search it
Explanation:
please mark me as a brainlist
In the system model, the direction of the
arrow tells you that
Answer: Answer b
Explanation:
What is the difference between concrete and cement?
Answer:
cement is actually an ingredient of concrete. Concrete is a mixture of aggregates and paste. ... Cement comprises from 10 to 15 percent of the concrete mix, by volume.
Based on the Lewis/electron dot representation
of the two atoms, predict the ratio of metal
cationic (+) atom to nonmetal anionic (-) atom in
the compound.
Be.
•As.
A. 1:3
B. 2:1
C. 3:2
D. 1:1
Answer the ratio of Be to At is 1:2 in the compound
Explanation:
Be in Periodic Table 2A has 2 valence electrons in its outer orbital and needs to give them away. When it gets rid of 2 negatives, its charge is +2.
At in Periodic Table 7A has 7 valence electrons in it outer orbitals and needs one more electron. 2 AT atoms each accept one electron from Be and each has a charge of -1. The Be ion of +2 charge is balanced by the two At ions of -1 charge, so the ratio of Be to At is 1:2
A substance is a base if it has a pH value greater than___
PLEASE ANSWER ASAP
Answer:
A substance is basic or alkaline if it's pH is greater than 7.0.
which statement about the carbon cycle are correct
1. carbon dioxide is added to the atmosphere by respiration
2. carbon dioxide is added to the atmosphere by combustion of coal
3. carbon dioxide is removed from the atmosphere by photosynthesis
pick 2!
While considering boiling point elevation and freezing point depression a solution concentration is expressed in molality and not in molarity?why?
Answer:
Colligative properties are physical properties of solutions, like boiling point elevation and freezing point depression. In these calculations, the temperature of the solution is changing as we add more solute to the solvent, so this means that the volume of the solution is changing. Since molarity is moles solute per liter of solution, we cannot use molarity as our concentration unit. This is why we use molality (moles solute per kg of solvent) since the kg of solvent doesn't change with temperature.
Explanation:
First in boiling point elevation and freezing point depression, we deal with the system whose temperature is not constant. Second we cannot express the concentration of the solution in mortality because it changes with temperature whereas mortality is temperature independent. Therefore, while considering boiling point elevation and freezing point depression a solution concentration is expressed in mortality and not in mortality.
True or false: Everything is either matter or energy.
Answer:
It is true
Explanation:
Matter is anything that has mass and occupies safe.
Energy is the ability to cause change or do work,and some forms of energy include nuclear,heat, chemical,light, mechanical energy and electrical energy.
One source of renewable energy is ocean waves. A machine like the one shown below can convert energy from ocean waves into electricity. This machine floats on the surface of the water.
a long piece of machinery in the ocean
In which situation would the generator be able to produce more electricity?
A.
The distance between wave crests increases.
B.
The time between wave crests increases.
C.
The depth of the water beneath the waves increases.
D.
The average height of each wave increases.
The situation in which the generator is able to produce more electricity is option D, the average height of each wave increases.
What is water wave?Water wave is a type of mechanical wave. Water wave is a transverse wave in which the oscillation of particles is along the direction of wave propagation.
The the water waves are highly energetic and this kinetic energy is converted to electric energy using turbines and generator. The height to the crest of the wave from the base line is called amplitude. As the amplitude increases, energy of the wave is increasing.
Thus, more the amplitude, more the energy of wave leading to greater yield of electrical energy as well. Therefore, option D is correct.
Find more on water waves:
https://brainly.com/question/23269505
#SPJ2
which of these is not recovered through dry heating(evaporation)
The correct answer is C
Brainliest?
Which of the following can survive either with oxygen or with out it
Facultative anaerobes.
Organisms that grow in the absence of free oxygen are termed anaerobes; those that grow only in the absence of oxygen are obligate, or strict, anaerobes. Some species, called facultative anaerobes, are able to grow either with or without free oxygen.
- BRAINLIEST answerer ❤️✌
The density of alcohol is 0.91 g/mL. What volume would 312 g of alcohol occupy?
Volume = Mass ÷ Density
= 312 g ÷ 0.91 g/mL
= 342.86 mL
∴ the volume of alcohol is 342.86 mL.
Question 10 (5 points) (02.04 LO Which of the following most likely causes the particles in a chemical reaction to slow down? (5 points) Ralsing the thermal energy of the particles DU a Ob Increasing the rate of the reaction OC Lowering the temperature Od Adding heat to the reaction
Answer:
C Lowering the temperature
Explanation:
The force excerted by air molecules in all directions is called
what makes viruses so dangerous and vaccines so importent
Answer:
they are very dangerous.
Explanation:
they cause disease in humans, animals, crops, and can cause permanent damage to immune systems.
Answer:
viruses can shut your immune system and infect blood cells thus killing you. vaccines will provent this by prepering your immune system so when you get said virus, it will reduce your chance of death
Explanation:
im not smart with health but i hope this is correct!
Frank has a paper clip. It has a mass of 9g and a volume of 3cm³. What is the density
What is the end result
of diffusion?
Answer:
The End Result Of Diffusion Is An Equal Concentration, Or Equilibrium, Of Mocules On Both Sides Of The Membrane.
Explanation:
☺️ Hope It helps Ty.
Of the groups given, which are the least chemically reactive?
Group 1A elements
Group 7A elements
Group 2A elements
Group 8A elements
Answer:
Group 8A
Explanation:
This is because the elements in Group 8A is stable, what I mean is this elements have the maximum number of electrons in there last orbit so they dont need to form any compund with any other element in the periodic table.
HOPE THIS WILL HELP YOU❤️
Animals can get nitrogen by eating _____ and then making their own protein.
plants
gases
minerals
waste
Answer:
plants
Explanation:
Animals get the nitrogen they need by eating plants or other animals that contain nitrogen. When organisms die, their bodies decompose bringing the nitrogen into soil on land or into ocean water. Bacteria alter the nitrogen into a form that plants are able to use.
Hope this helps :)
Describe how
ions impact functions
in the heart
Explanation:
In a normal heart, there is a balance between calcium and potassium ion levels in both the outer and inner walls of the heart. That balance keeps electrical energy flowing correctly through the heart, and allows the heart muscle to expand and contract as the heart beats.10-Nov-2005
https://www.
+++TO BE ANSWERED ASAP (WILL PUT BRAINLIEST!!!)+++
What does it mean that the filtered water samples reacted with phenolphthalein?
Answer:
Phenolphthalein is an acid indicator, which means when we add water (pH 7) to it, it ionizes giving a pink color. We all know acid gives in solution. When we add phenolphthalein to acid due to the common ion effect concentration increases. turned the solution pink.
Explanation:
The faster the particles, the
______ the temperature.
Less forceful
Slower
Higher
Lower
Answer:
When for example, heating up an ice cube the particles of the ice start to vibrate fast enough to get separated into liquid caused from high temperature. So the answer is Higher.
what is the use of PVC
Answer:
PVC is a versatile material that offers many possible applications, these include; window frames, drainage pipe, water service pipe, medical devices, blood storage bags, cable and wire insulation, resilient flooring, roofing membranes, stationary, automotive interiors and seat coverings, fashion and footwear, packaging .
Explanation:
How do valence electrons impact the type of bonds an atom makes?
An atom wants an empty outer shell of valence electrons, so it will either transfer or share electrons depending on what the other atom needs.
A large number of valence electrons means the atom will share electrons; a small number of valence electrons leads to transferring from one atom to another.
A small number of valence electrons means the atom will share electrons; a large number of valence electrons leads to transferring from one atom to another.
An atom wants a full outer shell of valence electrons, so it will either transfer or share electrons depending on what the other atom needs.
Use your knowledge of valence electrons and how they affect bonds to figure out how carbon (Group 14) and oxygen (Group 16) would be attached to one another. In carbon dioxide (CO2), how is the compound structured? (Use “–” to represent a single bond and “=” to represent a double bond.)(1 point)
O=C=O
C=O–O
C–O–O
O=C–O
Methane’s chemical formula is CH4. Is there a bond between any of the hydrogen atoms? Why or why not?
Yes, there is because there are one too many hydrogen atoms for carbon to handle alone, so one hydrogen must bond with another.
No, there is not because carbon needs four bonds, so it bonds with each hydrogen atom; hydrogen only forms one bond.
No, there is not because it would form H2 instead of methane if hydrogen bonded with itself.
Yes, there is because they form a long chain in order to all have stable outer energy shells.
In hydrogen peroxide (H2O2), which option best shows how the atoms are ordered?
H–O–O–H
O–H–H–O
H–O–H–O
O–H–O–H
Answer:
1) two
2) an atom wants a full outer shell of valence electrons, so it will either transfer or share electrons depending on what the other atom needs
3) O=C=O
4) No, there is not because carbon needs four bonds, so it bonds with each-
5) H-O-O-H
Explanation:
Answer: 1) two
2) an atom wants a full outer shell of valence electrons, so it will either transfer or share electrons depending on what the other atom needs
3) O=C=O
4) No, there is not because carbon needs four bonds, so it bonds with each-
5) H-O-O-H
Why does the reactivity of metals increase from right to left on the periodic table? (1 point)
Metals on the right have more valence energy levels, so the ability of the nucleus to attract electrons is reduced,
Metals on the right have more protons, causing valence electrons to be held more strongly
Metals on the right have fewer protons, making it harder to attract electrons from other atoms,
Metals on the right have fewer valence energy levels, so electrons are closer to the nucleus and harder to pull away
3
TH
Type here to search
09
Taking into account the definition of reactivity, the correct option is the first option: Metals on the right have more valence energy levels, so the ability of the nucleus to attract electrons is reduced.
Reactivity is a measure of the probability that a chemical species will participate in a chemical reaction to form chemical bonds.
In other words, the reactivity of a chemical element is the tendency that this element has to combine with others.
For elements that behave like metals, this trend is directly related to the ease with which they lose their valence electrons.
Valence electrons are those electrons farthest from the nucleus of the atom. These electrons are easier to remove because they are the least attracted to the nucleus. Thus, less and less energy is needed to start these valence electrons, so they can commonly participate in the formation of chemical bonds.
In other words, as the size of the metal atoms in a group increases, so does their reactivity.
Then, the correct option is the first option: Metals on the right have more valence energy levels, so the ability of the nucleus to attract electrons is reduced.
Learn more:
https://brainly.com/question/25163860?referrer=searchResultsHow do elements heavier than iron form?
Answer:
neutron captureExplanation:
Hope this helps :)
Pls make brainliest :3
And have an amazing day <3
What is Protein coat
Answer: virology) A coat of proteins surrounding the nucleic acid of a virus. Supplement. The protein coat is made up of protein subunits called capsomere. Additional layer of lipid molecules may envelope the protein coat.
Explanation: