Answer:
Protons = 11
Electrons = 10
Neutrons = 12
Explanation:
The atomic number of an element is the number of protons present in the nucleus of an atom of that element. A neutral atom of an element contains equal number of protons and electrons, therefore, the atomic number is also the electron number for a neutral atom.
The mass number is the sum of proton and neutrons in the nucleus of an atom of an element.
The atomic number of sodium-23, Na-23 is 11 while the mass number is 23.
An atom of sodium that has a net charge of +1 has lost an electron. Therefore, from the above information, the number of protons, neutrons and electrons present in this atom of sodium-23 is as follows:
Protons = 11
Electrons = 11 - 1
Electrons = 10
Neutrons = 23 - 11
Neutrons = 12
Which elements are;
a)solids,
b)liquids
c)gases
at 25°C
The empirical formulae of a compound is CH2O. The relative formula mass for the molecular formula is 180. What is the molecular formula?
Answer:
ch20 is the empirical formula for glucose , c6h1206 is the molecular formula .
A prokaryotic cell does not have
А
a cell membrane.
B
genetic material.
C
a nucleus.
D
flagella.
Answer:
D
Explanation:
I need help in this questions
Answer:
just use calculator mannn
Label each process as a physical or chemical change and state how you know.
fogging a mirror with your breath
breaking a bone
mending a broken bone
burning paper
slicing potatoes for fries
mixing sugar with coffee
frying chicken
a nail rusting
paper ripping
wood burning
mixing water and food coloring
food molding (rotting)
writing on paper
dyeing fabric
Fogging a mirror with your breath is a physical change because it involves a phase change of water vapor condensing and adsorbing to the mirror surface. Phase changes are physical changes.
Breaking a bone is a physical change insofar as we're focusing on the "breaking" part.
Mending a broken bone, however, is a different story. Bones are living things: They consist of tissues that in turn consist of cells. The actual mending process involves some very complicated biochemistry. Suffice it to say that mending a broken bone would be a chemical change.
Burning paper is a chemical change. Burning anything implies combustion, which is a chemical reaction where some fuel is oxidized (usually by oxygen gas, producing carbon dioxide gas and water vapor).
Slicing potatoes for fries is a physical change. You can slice, dice, smash, mash, stretch, bend, compress, or grind a potato: What you will have is still a potato (okay, there are some chemical changes going on as you're rupturing cells in the process, causing them to release their contents which may participate in chemical reactions). But the key, again, is that cutting up some material doesn't fundamentally change the chemical identity of that material.
Mixing sugar with coffee actually involves two physical processes: the mixing and the (presumed) solvation of the solid sugar particles as they dissolve into the coffee. In either case, either mixing or dissolving would be a physical change. The sugar molecules are still in the coffee and are chemically unchanged.
Frying chicken is a chemical change. In fact, frying chicken likely entails several different types of chemical changes. The common thread among them is that frying involves breaking chemical bonds in and on the chicken by the addition of thermal energy, and new chemical bonds end up being formed. That's the hallmark of a chemical change.
A nail rusting is a chemical change. Rusting is an electrochemical process; the familiar corrosion of iron into rust is, at bottom, a chemical reaction where iron reacts with oxygen to form iron oxides (often catalyzed by the presence of water and salts).
A paper ripping is analogous to slicing potatoes: it's a physical change. If you ripped one sheet of paper into two halves, each half would retain all the chemical properties of the original sheet.
Likewise, wood burning is analogous to burning paper, and as such is a chemical change. Again, combustion is a chemical process.
As we said earlier with sugar in coffee, mixing in itself is a physical process. While it may seem like you've permanently changed the nature of the water by dyeing it with food coloring, the molecules comprising the food coloring are simply dispersed within the vast sea of water molecules. There are no intramolecular bonds that are broken or formed; the chemical identities of all the substances here are preserved. So, this is a physical change.
Food molding (rotting) is a chemical change. Rotting is biochemical decomposition: the chemical bonds that make up the food are broken down by enzymes released by the mold.
Writing on paper, whether it be with a pen, pencil, crayon, or marker, is a physical change. The molecules from the writing instrument are physically stuck to the paper. But unless you're writing on paper by, say, burning letters onto it, there are no chemical changes occurring when the writing instrument meets the paper.
As with writing on paper, dyeing fabric can be a physical change. The dye consists of molecules that interact with light in a way that we perceive a certain color. When dyeing fabric, these molecules are transferred and fixed into the fabric by adsorption, absorption, and other intermolecular phenomena. But the molecules of the dye (and the molecules in the fabric) don't experience any breaking and forming of bonds. All of the substances involved retain their chemical identities.
However, it's possible that, depending on the dye, there may be chemical changes involved. Some dyes, appropriate named "reactive dyes," undergo chemical reactions with their substrate (which, in this case, would be the fabric), or dyes may be used that undergo chemical reactions with one another, both of which would constitute chemical changes. And it can depend on what you mean by "dyeing": Bleaching a colored shirt can technically be conceived of as "dyeing" the shirt white, and this process involves cleavage of bonds within the color-producing molecules in the fabric by reacting with the molecules in the bleach.
So, for dyeing fabric, it can be a physical or chemical change depending on the dye.
What affects both deep water and surface currents in the ocean?
Answer:
These currents are on the ocean's surface and in its depths, flowing both locally and globally. Winds, water density, and tides all drive ocean currents. Coastal and sea floor features influence their location, direction, and speed. Earth's rotation results in the Coriolis effect which also influences ocean currents. -
Answer: The Coriolis effect
Explanation:
The charge of a single proton is 1.60 × 10–19 C. What is the nuclear charge of an atom of boron (B)?
Answer:
[tex]q=8\times 10^{-19}\ C[/tex]
Explanation:
Given that,
The charge of a single proton is [tex]1.6\times 10^{-19}\ C[/tex]
There are 5 protons in the nucleus. The nuclear charge of an atom of boron is given by :
[tex]q=5\times 1.6\times 10^{-19}\\\\q=8\times 10^{-19}\ C[/tex]
So, the required charge is [tex]8\times 10^{-19}\ C[/tex].
1. Which of the following statements is true about seeds?
a. Every plant produces seeds.
c. All seeds are good to eat.
b. All fruits contain many of seeds. d. all seeds has young plant, stored food and a seed coat.
2. Flowers cannot usually produce seeds unless
a. they are visited by insects.
c. they produce nectar.
b. they are on plants growing in good soil. d. the right pollen is placed on their stigmas.
3. Fertilization take place before a seed develops. Which statement describes when fertilization
occurs?
a pollen grain falls on a pistil
c. sperm in a pollen joins with an egg cell in an ovule
b. a pollen tube enters an ovary
d. an ovary becomes a fruit
4. Which of the following is NOT a factor needed by plants?
a. fire
b. nutrients
Please pasagot po ng tanong ko please
c. sunlight
d. water
5. Which is the reproduction in plants where the male and female parts of the flower are involved?
a. asexual
b. sexual
c. rhizome
d. pollination
Answer:
1 ans: d. all seeds has young plant, stored food and a seed coat.
2 ans: d. the right pollen is placed on their stigmas
3 ans: a. pollen grain falls on a pistil
4 ans: a. fire
5 ans: b. sexual
Hope it helps,
Please mark me as brainliest
Thank you...
When a gas is heated, the gas particles have more kinetic energy. Complete the following sentence: This means they move about more and have more ______ with the sides of the container. This increases the pressure.
Answer:
Contact
Explanation:
As the speed of the particles increases, they move around more, which means they hit the sides of the container more.
What’s the answer for this question
Answer:
i think it's B
Explanation:
What experiment did J. J. Thomson do?
A. He sent a cathode ray between electrically charged metal plates.
B. He suspended charged oil drops in a chamber.
C. He hit metal plates with light.
D. He shot alpha particles through gold foil
Answer:
A. He sent a cathode ray between electrically charged metal plates
b Explain what would have happened if Jilly
had thrown the object with more force.
Answer:
force had thrown the object with more
Answer:
If an object is in motion and more force is applied to it, the object will begin moving faster
Explanation:
don't have any (sorry:[ )
A sample of gas at 3000.0mmHg inside a steel tank is cooled from 500.0°C to 0.00°C what is the final pressure of the gas in the steel tank
Answer:
1429.32 mmHg
Explanation:
Initial Pressure P1 = 3000.0mmHg
Initial Temperature T1 = 500.0°C + 273 = 573 K ( Converting to kelvin temperature)
Final Temperature T2 = 0.00°C + 273 = 273 K ( Converting to kelvin temperature)
Final Pressure P2 = ?
The pressure of a given amount of gas is directly proportional to the absolute temperature provided volume remains constant.
This is given by the mathematical expression;
P1 / T1 = P2 / T2
Inserting the values;
3000 / 573 = P2 / 273
P2 = 273 * 3000 / 573
P2 = 1429.32 mmHg
how do we know that a chemical reaction occured
Answer: signs of a chemical change are a change in color and the formation of bubbles. The five conditions of chemical change: color change, formation of a precipitate, formation of a gas, odor change, temperature change.
Explanation:
¯\_(ツ)_/¯(⌐■_■)(☞ﾟヮﾟ)☞☜(ﾟヮﾟ☜)
A molecule is
A a group of atoms bonded by ionic bonds.
B a group of atoms bonded by covalent bonds.
C a group of ions bonded by covalent bonds.
D a group of atoms bonded by metallic bonds.
Answer:
B.
Explanation:
Atoms make up molecules and ionic bonds cannot make up a molecule because they do not share electrons like in a covalent bond.
24. In our experiment, we filled 4 tubes with water and bromothymol blue.
Tube 1 did not contain an organisms, tube 2 contained a snail, tube 3
contained a elodea and tube 4 contained both a snail and elodea. What
tubes could photosynthesis occur in?
O Tubes 3 and 4
O Tubes 2 and 4
O Tubes 2, 3, and 4
Answer:
C. Tubes 2, 3, and 4
Explanation:
Tube one doesn't contain an organism so it can't be that one.
Both a snail and an elodea are considered an organism, cellular respiration occurs in almost any organism's cells.
good luck, i hope this helps :)
An atom that has lost one or more electrons is a(n) _____.
Not Cation
Answer:
ion
Explanation:
that is the definition according to g o o g l e:
"an atom or molecule with a net electric charge due to the loss or gain of one or more electrons."
Answer:
An ION
Explanation:
Because a positive ion is called a CATION and a negative ion is called an ANION (Please brainlist me)
A skateboarder coasts a distance of 20 meters in 4 seconds. What is the person's speed?
Answer:
5
Explanation:
20/4
How many moles are in 35.6 g of H2O
Answer:
Given
mass of H2O (m) =35.6g
molarmass (mr) = H2O ), 1x2+16=18g/mol
moles of H2O (n) =?
sln
n=m/mr
n=35.6g/18g/mol
n=1.978moles
the moles of H2O are 1.978moles
Why does oxygen have a higher electronegativity compared to chlorine?
Answer:
The electronegativity of fluorine compare to the electronegativity of oxygen and chlorine as below
Explanation:
Fluorine has the highest electronegativity than oxygen, and chlorine.
Explanation
Generally the electronegativity increase across the period ( from the left to the right) and decreases down the group.
Both oxygen and fluorine are in period 2 in periodic table. since fluorine is on fur right side as compared to oxygen , fluorine has higher electronegativity than oxygen.
On the other side Fluorine and chlorine are in the same group in periodic table. fluorine is at the top of the group while chlorine is at the bottom therefore fluorine has higher electronegativity than chlorine.
need asap!
The boiling point of hydrogen sulfide is low. Explain why.
Sulfur is not nearly as electronegative as oxygen so that hydrogen sulfide is not nearly as polar as water. Because of this, comparatively weak intermolecular forces exist for H2S and the melting and boiling points are much lower than they are in water.
The boiling point of hydrogen sulfide is low because the oxygen atom was stronger electronegative than that of the Sulphur atom, water would be more polar than hydrogen sulphide.
What is polar molecule?If a molecule does have more positive charges on one end than negative charges on the other, an electrical pole has been created. This is how polar molecules are typically formed.
What is boiling point?
The temperature where a liquid's vapor pressure reaches the pressure around it as well as the liquid transforms into a vapor is known as the boiling point of a substance.
The boiling point of hydrogen sulfide is low because the oxygen atom was stronger electronegative than that of the Sulphur atom, water would be more polar than hydrogen sulphide. Additionally, hydrogen sulphide has a lesser melting point as well as boiling point than water due to poor intermolecular forces (dipole forces, Vander Waal's forces).
To know more about polar molecule and boiling point
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what is the molar mass of Mg(NO2)2?
Answer:
116g/mol
Explanation:
Mg=24
NO2=46
multiple 46 by 2and then add 24
The molar mass of Mg(NO₂)₂ is 116.33 g/mol.
To calculate the molar mass of Mg(NO2)2, we need to determine the atomic masses of each element in the compound and multiply them by their respective subscripts.
The atomic masses of the elements involved are:
Mg (magnesium) = 24.31 g/mol
N (nitrogen) = 14.01 g/mol
O (oxygen) = 16.00 g/mol
The compound Mg(NO₂)₂ contains one magnesium atom (Mg), two nitrate ions (NO₂), and each nitrate ion contains one nitrogen atom (N) and two oxygen atoms (O).
Molar mass of Mg(NO₂)₂ :
Mg: 1 × 24.31 g/mol = 24.31 g/mol
N: 2 × 14.01 g/mol = 28.02 g/mol
O: 4 × 16.00 g/mol = 64.00 g/mol
Now, add up the individual masses:
24.31 g/mol + 28.02 g/mol + 64.00 g/mol = 116.33 g/mol
Therefore, the molar mass of Mg(NO₂)₂ is 116.33 g/mol.
Learn more about molar mass here:
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How many moles are in 4.0 x 1023 atoms of iron?
Answer:
4092 atoms of iron i am guessing
Explanation:
Balance the folowing equation.
S + 02
ws
SO:
Answer:
s+o2=so2
Explanation:
i hope it will help u
ZN + HCI —> ZnCI2+ H2
what is the reaction and is it balanced?
which of the following best explains why the strings of a harp make sounds when it is played?
What is the half-life of Technetium-99 if a 200 gram sample decays to 50 grams in 639,000 years?
Answer:
The half-life of Th-232 is 1.4 ∙ 10¹⁰ years.
Explain how the use of fossil fuels can cause lakes and ponds to become more acidic.
Answer:
Explained below
Explanation:
Fossil fuels which are made up of coal and oil when burnt by power-production industries, make sulfur to be released into the atmosphere where it combines with oxygen to form SO2 (sulfur Dioxide). Now, the exhausts possessed by cars could also cause the formation of nitrogen oxides in the atmosphere. Therefore, H2SO4 which is airborne sulfuric acid and HNO3 which is nitric acid can be formed and when dissolved in the water vapor in the atmosphere form what is called acid rain.
Now, as acid rain flows through the soil, it can leach aluminum from the soil clay particles and then flow into the lakes to make them more acidic.
The diagram shows a vertical number line. A vertical line with arrowheads at both ends has tick marks every 4 units with the tick marks for negative 4, 0, 8 labeled. The tick mark two past 8 has an X next to it. What is the position of point X? –16 –12 12 16
Answer:
16
Explanation:
Answer:
its 16
Explanation:
i took the quiz and it was right
(a) Give the H-C-O bond angle in methyl formate H-C-O bond angle methyl formate
(b) One dihedral angle in methyl formate relates the plane containing the O-C- O bonds to the plane y two structures of methyl formate: one in which this dihedral angle containing the Co-onds, identand the other in which it is 180 0° dihedral angle 80" dihedral angle.
Answer:
Explanation:
The bond angle is said to be the angle between two atoms near or around the same atom for a given covalent compound. However, a dihedral angle is known as the angle formed between two planes. Bond angles are usually planar while dihedral angles are interplanar.
The diagram below shows the structure of each compound.