Answer:
its atomic number will be 3 and it's mass number will be 7. it is lithium
please help me
Type the correct answer in the box. Spell all words correctly.
What does Dalton's atomic theory propose?
A ______ causes rearrangement of atoms.
Why does scientists use atomic watch?
Answer:
atomic watch
Explanation:
it is used for the measurement of time.
Nicole pushes her bike up a hill. Overhead, the sun exerts a gravitational force on Earth. Which statement is true about the bike and Earth?
They both experience contact forces.
They both experience non-contact forces.
The bike experiences a non-contact force and Earth experiences a contact force.
The bike experiences a contact force and Earth experiences a non-contact force.
Answer: c
Explanation:
What are their name?
Answer: Ch3 is Methlene Ch2 is Methyl Ch is Benzen
Explanation:
Hope this helps
What mass of KBr (in grams) do you need to make 250. 0 mL of a 1. 50 MKBr solution?.
Answer:
KBr final solution:
V = 250mL --> 0.25L
Concentration/Molarity = 1.5 mol/L
To find the amount of moles of KBr here, just multiply the volume by the concentration (0.25 x 1.5 = 0.375 mol)
So the amount of moles for KBr is 0.375 mol. Now we know that the mass divided by the molar mass (the atomic mass values of K and Br in the periodic table added together) would give us the amount of moles aswell.
n = moles
m = mass
M = molar mass
n = m/M
so if we rearrange this equation to find mass, we would get:
m = n x M
Molar mass for KBr: (39.09) of K + (79.90) of Br = 118.99
m = 0.375 mol x 118.99
m = 44.62g
Therefore 44.62g of KBr is needed to make 250mL of a 1.5 M KBr solution.
A gas measures 140 mL at 400 K find its volume at 120 K if the pressure remains constant.
By applying Charles law, the final volume of the gas is equal to 42 mL.
Given the following data:
Initial volume = 140 mLInitial temperature = 400 KFinal temperature = 120 KTo find the final volume of the gas, we would apply Charles law:
Charles law states that when the pressure of an ideal gas is kept constant, the volume of the gas is indirectly proportional to the absolute temperature of the gas.
Mathematically, Charles law is given by the formula;
[tex]\frac{V}{T} =k\\\\\frac{V_1}{T_1} = \frac{V_2}{T_2}[/tex]
Where;
T is the temperature of an ideal gas.V is the volume of an ideal gas.Substituting the given parameters into the formula, we have;
[tex]\frac{140}{400} = \frac{V_2}{120} \\\\140 \times 120 = 400V_2\\\\16800 = 400V_2\\\\V_2 = \frac{16800}{400}[/tex]
Final volume = 42 mL.
Read more on Charles law: https://brainly.com/question/22971882
the primary difference between enhancers and promoter-proximal elements is that enhancers _____.
Answer:
Enchancers are transcription factors
I hope that helps you
for which elements are outer electrons and valence electrons the same?
Answer:
The number of electrons in the outermost shell of a particular atom determines its reactivity, or tendency to form chemical bonds with other atoms. This outermost shell is known as the valence shell, and the electrons found in it are called valence electrons.
Explanation:
Elements of same group have same number of valence electrons and similar physical and chemical properties.
What are groups in periodic table ?A periodic table is classified into different columns and rows. The vertical columns in the table are called groups and the horizontal rows are called periods.
From left to right, the atomic number of elements increases by one and atomic size increases. Down a group, the number of electrons and atomic size as well increases.
Elements of same groups have same number of outer electrons or valence electrons. They show similarities in chemical and physical properties.
For example, lithium and sodium are in the first group. They both have one valence electron.
Find more on groups in periodic table :
https://brainly.com/question/7373020
#SPJ6
What is the periodic table?
Answer:
The periodic table, also known as the periodic table of chemical elements, is a tabular display of the chemical elements. It is widely used in chemistry, physics, and other sciences, and is generally seen as an icon of chemistry.
Explanation:
The periodic table is a tabular arrangement of chemical elements that classifies elements according to repeating qualities and is structured by increasing atomic number. Metals are located on the left side of the table, whereas nonmetals are located on the right. The columns are referred to as groupings.
in pic
____________________________________________________
(Hope this helps can I pls have brainlist (crown)
Can someone help me with this chemistry question please?
C. Energy use
please mark me a brainlist
Kinetic energy is described as
Question 1 options:
Movement
Decreasing energy
Stored energy
Elastic
Answer:
its the movement because kinetic energy means moving not stopping or decreasing
Explanation:
A watch loses 0.15 sec/min, how many seconds are lost in 24 hours?
Answer:
0.15 sec/min = 9 sec/hour
9*24 = 216 seconds = 3.6 minutes
Explanation:
Answer:
216 Seconds
Explanation:
If every minute is 60 seconds than 60 multiplied by .15 is 9 Seconds Lost.
If every hour is 60 minutes compared to what we know than 24 hours multiplied by 60 is 1440 minutes.
Do the same math as before: 1440 x .15 = 216 Seconds
( i will give you brainliest who ever answers the question first and the right answer!!!)
What do you predict would happen if you brought a negatively charged balloon next to an uncharged piece of paper?
A. The balloon will attract the paper.
B. The balloon will repel the paper.
C. Nothing will happen.
D. The paper will repel the balloon.
Answer: A
Explanation:
Answer:
B. The ballon will repel the paper
You want to build a deck off your kitchen and you estimate that you will need 3000 #8 nails all together. Rather than pay extra for them to be put in little boxes, you go to a hardware store where they sell nails in bulk. How does the sales clerk count out 3000 #8 nails for you?
Answer:
The sales clerk can count your nails in 6 groups of 500 nails, or 30 groups of 100 nails to ease the counting process and garauntee a more accurate result.
Explanation:
What do you put in the cavity of an unstuffed turkey?
what year did ernest rutherford make his discovery
Answer:
May, 1911: Rutherford and the Discovery of the Atomic Nucleus.
Explanation:
Mark me brainly please.
At what point on a heating curve graph does a phase change occur?
at each plateau
at the first plateau
at each slope
at the last slope
Answer:
Electrical Bonding Investigation Data Quick Check
Explanation:
B. Heat energy is added to the substance, weakening the electrica attraction between molecules.
C. Both the melting point and boiling point are lower
C. The lone pairs of electrons in the oxygen atom causes the molecule to be bent; the oxygen atom has a particle negative charge, while the hydrogen atom have particle positive charges
D. Phase change
C. At each plateau
Help Help Help Help Help Help Help Help Help Help Help Help Help Help Help Help Help Help Help Help Help Help
if the student finds the weight of the sodium chloride to be 28.5g,calculate the number of particles.(Na=23,Cl=35.5)
Answer:
2.93×10^23
Explanation:
molecular formula of NaCl is 58.5
58.5gof NaCl=6.023×10^23
28.5g of NaCl= 6.023×10^23÷58.5×28.5
= 2.93×10^23
What’s a conjugative Bas of OH-
Answer:
the answer is O²- hopefully
how many pairs of electrons are shared between two adjacent carbon atoms in a saturated hydrocarbon?
is a single cell the smallest structure that carries out our activities nesscesary for life
yep, the cell is the smallest unit in a living organism that is capable of carrying out all of the activities of life.
What increases the concentration of H+ in water ?
Answer:
Acid
Explanation:
Which two statements are true for both compounds and mixtures?
A. They are made up of more than one type of atom.
B. Their particles all have the same chemical formula.
O C. They can be separated into two or more elements.
D. Their particles are held together by chemical bonds.
Answer:
B and C is your best option
BRAINLIST ???
why does it make sense for the valence electrons to increase going across a period?
What's the Matter?
Which statements correctly describe matter? Select all that apply.
A. Matter is made up of atoms.
B. Matter is a measure of the amount of material in an object.
C. Matter may exist as a solid, liquid, or gas.
D. Matter forms when particles chemically bond together.
E. Matter includes both elements and compounds.
Answer:
Matter is anything that takes up space and has mass. Mass is the stu that matter is made of, or the amount of particles in a substance or object. Matter has physical and chemical properties and can undergo physical and chemical changes
C. Matter may exist as a solid, liquid, or gas.
Explanation:
When Newton started studying gravity, the concept of gravity was already in place.
A. True
B. False
how is the mode of data set defined
it is the middle value of the set
Answer:
No, mode isnt the middle value of a set that is median.
Explanation:
Mode (also known as modal class) is the value that appears most frequently in a data set.
can someone help me with this question!!
Answer:
A Because sodium chloride can break down the table sugar
Explanation:
hi
PLZ HELP i need it now