Answer:
18
Explanation:
In neutral atom protons and electrons are equal in number as it atomic number or proton number is 18 so electrons are also 18
The total number of electrons in an atom of an element with an atomic number of 18 and a mass number of 40 is 18.
What are the difference between atomic number and atomic mass ?Atomic mass can be defined as the total number of neutrons and protons located in nucleus of an element while atomic number is the number of protons present in the nucleus of element.
Atomic mass can be defined as the average weight of an element where as the atomic number is the total number of protons present in the nucleus; Atomic mass have the symbol A while atomic number have the symbol the letter Z.
Different isotopes of an element are differentiated by atomic mass is while isotopes share the same atomic number, in neutral atom protons and electrons are equal to atomic number or proton number is 18 and electrons are also 18
Learn more about atomic number, here:
brainly.com/question/8834373
#SPJ6
You are sitting in the central park bleachers of a Major League baseball park. You see a batter strike a pitched ball. About 0.4 seconds later you hear the contact between the bat and the ball. In terms of the properties of light and sound waves, how do you explain the difference in the communications you receivedbabout the same event?
Answer:
See the answer below
Explanation:
The speed of light in air and space is faster than the speed of sound in the same media. Light travels with a speed of approximately 3 x [tex]10^8[/tex] m/s while sound can only travel at 343 m/s (at 20 [tex]^oC[/tex]).
Consequently, the visuals of a batter striking a pitched ball which travel by light and is perceived through the eyes would be seen before the sound of the strike.
The difference in the speeds of light and that of sound largely explains the difference in the communication received about seeing a batter striking a pitched ball before hearing the sound of the strike
5. The compound is called:
*
(1 Point)
VP2
Vanadium (1) phosphide
Vanadium (IV) phosphide
Vanadium phosphide
Vanadium (VI) phosphide
Vanadium (V) phosphide
6. The compound is called
Answer:
Vanadium (VI) Phosphide
Explanation:
Vanadium has a 6+ charge for this compound, so there needs to be two phosphorus atoms to satisfy the charges. This is an ionic compound as well so the roman numerals need to be present.
A reaction begins with 130.5g of substance X and substance Y. How many grams of
substance X and Y are there at the end of the reaction?
A) not enough information provided
B) 100g
C) 65.25g
D) 130.5g
Answer:
130.5g
Explanation:
At the of the reaction, the combined mass of X and Y will be 130.5g.
The premise for this conclusion is based on the law of conservation of matter.
This law states that "in a chemical reaction, matter is neither created nor destroyed but changed from one form to another".
In essence, in a chemical reaction, there is no mass loss.
The amount of product in the reaction is expected to be the same as the amount of reactants used in the experiment. When we start with 130.5g then we should end with 130.5gWhat element is in period 6 with 2 valence electrons?
Answer:
Barium
Explanation:
I think that's the answer
The element in period 6 with 2 valence electrons is Barium.
The periodic table has been organized into periods and groups. The period is in an horizontal arrangement while group is vertical arrangement. The elements that can be found in period 6 are Beryllium, Magnesium, Calcium, Strontium, Barium etc. Elements in the same group have the same number of valence electrons. This means that elements in group 2 have 2 valence electrons. Barium possess two valence electrons because it is in group 2 and it is also in period 6. Therefore, the element in period 6 with 2 valence electrons is Barium.Learn more at: https://brainly.com/question/24089206?referrer=searchResults
A reversible reaction is said to be in equilibrium when
A)
all reactions stop leaving some reactant unused.
B)
the reaction goes to completion and no reactants are left.
9)
the rate of the backward reaction equals the rate of the forward reaction.
D)
the reaction rate of the backward reaction becomes larger than the rate of
the forward reaction.
Answer: C) the rate backward reaction equals the rate of the forward reaction.
Explanation:
Most of the elements on the Periodic Table are metals.
True
False
Answer:
the answer is true
Explanation:
I hope so it is helpful to u
Hair is composed of a protein called cellulose
O
True
O False
Answer:True
Explanation:
Iv done this before
what is the density of a liquid if it's volume is 125 mL and it's mass is 50g?
Answer:
0.4g/ml
Explanation:
density= mass/volume
density=50g/125ml
density=0.4g/ml
Does anyone know how to determine if a reaction is a redox or not?
2Ca+O2→2CaO2 is the reaction. I've already made it a balanced equation, I just need to determine if its a redox or not.
Thank you!
The reaction is included in a redox reaction
Further explanation:
Given
Reaction
2 Ca + O₂ → 2 CaO
Required
a redox reaction
Solution
Redox reactions are reactions where there is a change in oxidation number
Oxidation is an increase/increase in oxidation number, while reduction is a decrease/decrease in oxidation number.
Reducing agents are substances that experience oxidation and oxidizing agent are substances that experience reduction
in the above reaction is included in a redox reaction because there is a change in oxidation number
Ca⇒Ca²⁺+ 2e⁻(for balanced equation : 2Ca⇒2Ca²⁺+4e⁻)
Oxidation ( 0 to +2)
O₂+2e⁻⇒O²⁻(for balanced equation : O₂+4e⁻⇒2O²⁻)
Reduction (0 to -2)
FOR 50 POINTS & A BRAINIST*
1.) For an atom of sulfur, there are
A.) two electron shells with 6 valence electrons
B.) three electron shells with 6 valence electrons
C.) four electron shells with 6 valence electrons
D.) five electron shells with 6 valence electrons
2.) Which atom has four electron shells with 7 valence electrons?
A.) F
B.) CI
C.) Br
D.) I
3.) Which atom has three electron shells with 8 electrons in its outermost orbit?
A.) He
B.) Ne
C.) Ar
D.) Kr
4.) Which method should be used to draw electrons that are involved in a collision during a chemical reaction?
A.) Bohr's model
B.) Lewis dot model
C.) Addition model
D.) Subtraction model
Answer:
1. B
2. C
3. C
4. B
Explanation:
1. An atom of sulfur has an atomic number of 16. It has three electron shells and six valence electrons, therefore, it belongs to period 3, group VIA of the periodic table
2. Bromine has an atomic number of 35. It belongs to period 4 group VIIA of the periodic table. Therefore, it has four electron shells and seven valence electrons.
3. Argon has an atomic number of 18. It belongs to period 3, group IVA of the periodic table. Therefore, it has three electron shells and eight valence electrons.
4. The Lewis dot model use structures that represent the valence electrons of atoms within a molecule existing as lone pairs or when involved in bonding. They can be used to draw electrons that are involved in a collision during a chemical reaction.
Balance the following equation.
___ I + ___ O2 ___ I4O10
What goes in cellular respiration and what comes out of cellular respiration?
Oxygen and glucose are both reactants in the process of cellular respiration. The main product of cellular respiration is ATP; waste products include carbon dioxide and water.
How many atoms of S are in the following formula: 3Na(SO4)2
1) 6
2) 8
3) 3
4) 5
Answer:
6
Explanation:
Which of the following has the larger atomic radius?
O Cs
O Ca
O Li
O Ba
Hope it helps
Think about your morning from when you wake up until you arrive at school. Describe the forms of energy you encounter or use during that time. (Use types of energy like electrical, mechanical, thermal, etc)
Answer:
When sleeping the energy exhibited is Potential energy. When I wake up and I’m preparing for the day I use kinetic energy which is the energy exhibited during motion.
Eating before leaving the house means I used chemical energy for replenishment of nutrients to aid the performance of more activities for the day. The food eaten and the physical activities also give rise to thermal energy which is why we sweat.
Which is a component of John Dalton’s atomic theory?
The ratio of atoms in a compound is fixed.
The atoms of different elements are the same.
An atom is a small particle of matter that can be broken down.
A reaction can create or destroy atoms as well as rearrange them.
Answer: lol the answer is A
Explanation:
i’m just smart like that , thought i should give y’all a clue
Answer:
The ratio of atoms in a compound is fixed.
Explanation:
its a
How much work is required to pull a sled if you use 60J of work in 5 seconds?
Answer:
DO I Look Like santa too you how am i supposed to know How about this how about you goo.gle the answer wow smart
Explanation:
How many grams of CaCI2 (molar mass = 111 g/mol) are needed to prepare 100.mL of 0.100 M CI-(aq) ions?
a.) 0.555 g
b.) 1.11 g
c.) 2.22 g
d.) 5.55 g
I will mark as brainliest if you give the correct answer (brief explanation only, no worries)
Answer:
a
Explanation:
Because that is the answer
is bird seed homogeneous or heterogeneous
Answer:
heterogeneous
In order to give birds a varied and balanced diet, commercial bird seed blends typically include a range of seeds, grains, and other substances. As a result, bird seed is frequently categorised as a heterogeneous blend.
A seed is referred to as homogenous if its genetic makeup, size, shape, and other traits are all consistent. To guarantee consistency in the ensuing plants, these seeds are typically created through controlled breeding or genetic manipulation. A heterogeneous seed, on the other hand, is one that varies in genetic makeup, size, shape, and attributes. These seeds frequently result from cross-pollination or natural pollination between various species or kinds.
To know more about heterogeneous seed, here:
https://brainly.com/question/30583932
#SPJ6
I will give you Brainly if you awser correct if your gonna awser for points pl put I don’t know
Answer:
C
Explanation:
at the left.
6.
1. Work equals
A force x distance
B. force - distance
C. force + distance.
The force you apply to a machine
is the
A. input force.
B. output force.
C. efficiency.
2.
The unit of work is the
A. watt.
B. newton.
C. joule.
7.
The efficiency of all real
machines is
A. greater than 100%
B. equal to 100%
C. less than 100%
3.
Power is the amount of
A. work done per unit of time.
B. force on a certain area.
C. pressure in a volume of liquid.
8.
4.
The unit for power is the
A. joule.
B. Meter per second
C. watt.
The fixed point that a lever rotates
around is called the
A. fulcrum.
B. input force.
C. wedge.
9.
5.
A machine cannot change the
A. direction of the input force.
B. amount of work needed to do
A screwdriver is an example of a
simple machine called a
A. pulley.
B. screw
C. wheel and axle.
a task.
C. distance over which a force
is applied
10.
Your front teeth are
A. wedges.
B. levers.
C. compound machines.
Answer:
i know right answer
Explanation:
let me explain
A neutral atom of beryllium (Be) has an average mass of 9 amu and 4 electrons. How many neutrons does it have?
13
5
9
4
Answer:
It has 5 neutrons
Explanation:
The fact that it is a neutral atom tells us that the number of electrons and protons is the same:
The problem tells us there are 4 electrons, thus there are 4 protons.The average mass of an atom is the sum of the number of protons and the number of neutrons:
Mass = # Protons + # NeutronsWith the above information in mind we can calculate the number of neutrons:
9 amu = 4 Protons + # Neutrons# Neurons = 5 Neutronstwo or more atoms joined together form a _______
Answer:
When two atoms join together they make compounds
Explanation:
A molecule is formed when two or more atoms join together chemically. If atoms combine that are of two or more different elements, we call that a compound. All compounds are molecules, but not all molecules are compounds.
Determine the number of moles in 5.25x1024 formula units if lead (IV) oxide.
Answer:
8.72 mol PbO₂
General Formulas and Concepts:
Chemistry - Atomic Structure
Using Dimensional AnalysisAvogadro's Number - 6.022 × 10²³ atoms, molecules, formula units, etc.Explanation:
Step 1: Define
5.25 × 10²⁴ formula units PbO₂
Step 2: Identify Conversions
Avogadro's Number
Step 3: Convert
[tex]5.25 \cdot 10^{24} \ formula \ units \ PbO_2(\frac{1 \ mol \ PbO_2}{6.022 \cdot 10^{23} \ formula \ units \ PbO_2} )[/tex] = 8.71803 mol PbO₂
Step 4: Check
We are given 3 sig figs. Follow sig fig rules and round.
8.71803 mol PbO₂ ≈ 8.72 mol PbO₂
When an ionic bond forms what type of ions are joined?
Please answer these. The tables needed for question 7 are in the picture. I got rid of some of the questions that you wouldn’t be able to answer without doing the lesson
Question 1: Electron Notation Example (2 points)
a. Give the electron configuration of vanadium (V), atomic number 23. (0.5 points)
b. Give the noble gas configuration of vanadium (V), atomic number 23. (0.5 points)
c. List the energy levels for the orbital configuration of vanadium (V), atomic number 23. (1 point)
Question 3: Trends on the Periodic Table (2 points)
a. How does the atomic radius change going down and across the periodic table? (0.5 points)
b. How does first ionization energy change going down and across the periodic table? (0.5 points)
c. How does electronegativity change going down and across the periodic table? (0.5 points)
d. How does the radius of a positive and negative ion compare to a neutral atom? (0.5 points)
Question 4: Chemical Bonds (1 point)
Match each chemical bond to its correct description. (1 point)
A. Ionic bond ___ Sharing of electrons
B. Covalent bond ___ Freely moving electrons
C. Metallic bond ___ Transfer of electrons
Question 5: Intermolecular Forces (3 points)
a. Describe the dipole-dipole force. (1 point)
b. Describe hydrogen bonding. (1 point)
c. Describe the Van der Waals forces. (1 point)
Question 6: Intermolecular Forces and You (2 points)
Imagine you need to take a medicine that the doctor has prescribed for you. Explain why scientists who developed that medicine would need to know whether or not the compound in that medicine is polar. How might a polar medicine behave differently within your body than a nonpolar medicine would? Answer in 1 to 2 paragraphs.
Question 7: Energy in Bonds (9 points)
Use these tables for reference for all parts of this question.
This table summarizes the average energies of single bonds between atom pairs in many different compounds.
a. According to Table 2, which is the strongest bond? Which is the weakest bond? Based on what you know about the atomic radii and electronegativity of the elements involved in the bonds, why do you think these two have the most extreme bond-energy values? (3 points)
b. How are the bond energies of each bond listed in Table 2 determined? (1 point)
c. Why do you think there aren't bond energy values given in Table 2 for N–S and S–I? (1 point)
d. Based on Tables 1 and 2, how would you describe the trend in bond strength of single, double, and triple bonds? (1 point)
e. Based on Table 2, how would you describe the trend in the strength of bonds formed by the elements carbon, nitrogen, and oxygen? Would you describe this trend as a periodic trend? Why or why not? (3 points)
Question 8: Causes of Molecular Shape (3 points)
a. What is the VSEPR theory? (1 point)
b. How does electron repulsion determine molecular shape? (1 point)
c. How do lone electron pairs affect molecular shape? (1 point)
Question 10: Lewis Structure (3 points)
a. Draw the Lewis structure for the Se and 2 H atoms. (1 point)
b. Draw the Lewis structure for the SeH2 molecule. (1 point)
c. What shape would SeH2 have? Draw the molecule. (1 point)
Question 11: Ionic and Covalent Compounds (5 points)
Identify each of the following as a covalent compound or ionic compound. Then provide either the formula for compounds identified by name or the name for those identified by formula. (1 point each)
a. Li2O:
b. Dinitrogen trioxide:
c. PCl3:
d. Manganese(III) oxide:
e. Calcium bromide:
Two or more than two atoms with different physical or chemical properties can not combine together to form an element. Therefore, the electronic configuration of vanadium is 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d³.
What is element?Element generally consist of atoms or we can atoms combine to form element. Atoms of an element is always same, means all the properties of all atoms of one type of element is same.
The systematic distribution of electrons in the various atomic orbitals is called its electronic configuration. The atomic number of vanadium is 23. The electronic configuration of vanadium is 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d³. The noble gas electronic configuration of vanadium is [Ar]3d³4s². 1,2,3 represents the number of shells and s and represents the orbitals. The superscripts represents the number of electrons in each orbitals.
Therefore, the electronic configuration of vanadium is 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d³.
To know more about element, here:
brainly.com/question/8460633
#SPJ2
Think about how particles are arranged inside atoms. Please name and describe those three particles, and describe how the particles are arranged inside atoms. Some topics to include are: the charge of the particles, the mass of the particles, and where the particles are located.
The
the surface area of the reactants, the faster the reaction rate.
A. greater
B. lesser
where information about each element is located
Answer:
On the pereiodic table.
Explanation:
How are Earth's continents related?
Please help due at 11:45!