Answer:
Atomic Number: 27 (Co, Cobalt)
Explanation:
4s2 is before 3d7*
10. (a) Describe how the structure of an alloy is different to a pure metal
You can type directly into this text box below: (2)
10. (b) Suggest why coins are not made of pure copper. Do not give cost as a reason.
You can type directly into this text box below: (1)
Grade 5+ 15 marks
Total 27 marks
Um, yea, please help lol
Determine the volume of water to be added to the nitric acid solution at a concentration of 8.61 mol / L to prepare 500 mL of the bulk concentration solution at 1.75 mol / L
Answer:
398 mL
Explanation:
Using the equation for molarity,
C₁V₁ = C₂V₂ where C₁ = concentration before adding water = 8.61 mol/L and V₁ = volume before adding water, C₂ = concentration after adding water = 1.75 mol/L and V₂ = volume after adding water = 500 mL = 0.5 L
V₂ = V₁ + V' where V' = volume of water added.
So, From C₁V₁ = C₂V₂
V₁ = C₂V₂/C₁
= 1.75 mol/L × 0.5 L ÷ 8.61 mol/L
= 0.875 mol/8.61 mol/L
= 0.102 L
So, V₂ = V₁ + V'
0.5 L = 0.102 L + V'
V' = 0.5 L - 0.102 L
= 0.398 L
= 398 mL
So, we need to add 398 mL of water to the nitric solution.
Chemical Equations and Reactions WS
Answer:
1,1,1
decomposition reaction
Explanation:
The reaction equation is given as:
_Ca(OH)₂ → _CaO + _H₂O
This reaction is a decomposition reaction in which a single reactant breaks down to give two or more products.
To balance the equation, we assign variables a, b and c, then we use a mathematical approach to solve the problem;
aCa(OH)₂ → bCaO + cH₂O
Conserving Ca : a = b
O: 2a = b + c
H: 2a = 2c
let a = 1, b = 1 , c = 1
Alexandra is researching the effects of plate tectonics have on the shape of the earth. Which of the following is a result of plate tectonics
a. The species of grass on an island
b. Formation of mountains on land
c. Earths core temperature
d. The amount of precipitation over oceans
(Science)
Answer:
b
Explanation:
the plates crash into each other and form a mountain yea that's it
Convert the following number from scientific notation to standard notation:
7.80 x 105
Answer:
Call of balls massive sack
Explanation:
Yoooo
The diagram shows ice being heated on a stove over time. What is the sequence of the states of matter as the ice is
being heated?
A)
Process 1: solid to gas and Process 2 gas to liquid
B)
Process 1: solid to gas and Process 2: liquid to gas
Process 1: solid to liquid and Process 2: gas to liquid
D)
Process 1. solid to liquid and Process 2: liquid to gas
Answer:
The correct answer is D
Explanation:
Ice is a solid, so if heat is added to it the ice will melt causing it to form into a liquid, once the ice turns into a liquid, it begins to turn into gas.
Your welcome!
Someone help Match them
137g of Ba + ______ g oh I --> 391g of BaI2
Answer:
Explanation:
Is it worth it? Joy
As you move from the top to the bottom of the periodic table
Answer:
From top to bottom down a group, electronegativity decreases. This is because atomic number increases down a group.
Answer:
From top to bottom down a group, electronegativity decreases. This is because atomic number increases down a group, and thus there is an increased distance between the valence electrons and nucleus, or a greater atomic radius.
Explanation:
Why do all measurements have a degree of uncertainty?
Answer:
All measurements have a degree of uncertaintyregardless of precision and accuracy. This is caused by two factors, the limitation of the measuring instrument (systematic error) and the skill of the experimenter making the measurements (random error).
hellooo brainlyyyyyyy waddammmm
Answer:
Hallo whats up?
Explanation:
PLEASE HELP
Which reagent is the limiting reagent in a reaction?
Answer:
I believe B
Explanation:
Hope this helps
If a plant has a total of 17g of carbon dioxide and water reacting in photosynthesis, then how much glucose and oxygen will the plant produce?
A. 8.5g
B. 34g
C. 17g
(Take your time)
Answer:
Basically it would be 8.5g. Not total sure.
Explanation:
If its right plz give brainlest.
Answer:
A. 8.5g
Explanation:
Have a great day!
What could you say about the melting point of CO2?
O None of these answers are correct
O I'm not sure CO2 isn't an ionic compound.
O CO2 doesn't melt
O high melting point
Answer:
None of these answers are correct.
CO2 is a covalent not ionic compound
It DOES melt, though at a very low temperature
Its melting point is negative, not high
Explanation:
Chemistry. Question is on photo. Will mark Brainy for whoever gets this right.
Answer:
49.18 eV hope this helps
student plans to isolate chlorophyll, mix it in a solution of carbon dioxide and water, and then shine light on the mixture. Do you predict glucose will be produced inside the mixture
Answer:
No
Explanation:
In order for glucose to be produced inside the mixture, photosynthesis has to take place. The photosynthetic process requires a series of steps within an organelle called the chloroplast. The chloroplast contains the chlorophyll and other enzymes that are necessary for photosynthesis.
Once the chlorophyll is isolated, it becomes separated from the enzymes necessary for the completion of photosynthesis, and the process is truncated. When light is shined on the mixture, the majority would instead be lost as heat while some cause the chlorophyll molecules to glow.
__________________ to represent dominant alleles and used __________________ ___________________ to represent recessive alleles.
Answer:
Explanation:
Mendel used letters to represent dominant and recessive factors. Likewise, geneticists now use letters to represent alleles. Capital letters refer to dominant alleles, and lowercase letters refer to recessive alleles.
Write a question you have about water
Answer:
How many gallons of water are on earth?
Why does salt water make you sticky and burn our eyes so bad?
Explanation:
These are just a couple questions I came up with just now
I hope that this helps
An atom of an unknown element contains 17 protons and 19 neutrons. The total number of electrons present in a neutral atom of this element is
Answer:
This isotope of fluorine has 9 protons, 9 electrons and 10 neutrons.
Explanation:
The atomic number is the number of protons ( p + ) . In a neutral atom, the number of electrons ( e − ) equals the number of protons. Mass number is the sum of the protons and neutrons ( n 0 ) of a particular isotope. If you have mass number and atomic number, subtract the atomic number from the mass number to get the number of neutrons. ( Mass number ) − ( atomic number ) = number of neutrons .
There are:
9 protons
9 electrons
10 neutrons
Fluorine is the element in question, as its atomic number is 9 . You would name this particular isotope using the mass number. It would be called fluorine-19.
The nuclear or isotopic notation would be 19 9 F
This planet has the largest temperature range in the solar system.
O Mercury
O Venus
O Earth
O Mars
Answer:
Mercury did u want me to explain or u wanted the answer
Explanation:
what is PH??
i will mark as brainlest for best answer
Explanation:
pH is a scale used to specify the acidity or basicity of an aqueous solution. Acidic solutions are measured to have lower pH values than basic or alkaline solutions. The pH scale is logarithmic and inversely indicates the concentration of hydrogen ions in the solution.
1. How many moles of magnesium is 3.01 x 10^23 atoms of magnesium?
Answer:
0.5 molesExplanation:
To find the number of moles in a substance given it's number of entities we use the formula
[tex]n = \frac{N}{L} \\[/tex]
where n is the number of moles
N is the number of entities
L is the Avogadro's constant which is
6.02 × 10²³ entities
From the question we have
[tex]n = \frac{3.01 \times {10}^{23} }{6.02 \times {10}^{23} } = \frac{3.01}{6.02} = 0.5 \\ [/tex]
We have the final answer as
0.5 molesHope this helps you
Which is not considered a water flow?
If the size of an object decreases, volume does what?
Answer:
I'm pretty sure the volume decreases because the volume is like how much space it takes up. Sorry if im wrong.
How many moles are in 20g of potassium (K)?
Explanation:
Hi for this one u just need to remember and use the equation.
[tex]moles = \frac{mass}{mr} [/tex]
then u find mr of potassium which is 39.1.
then u do
[tex] \frac{20}{39.1} [/tex]
you get the answer as 0.5115 write ur answer to 3 significant figures which will be 0.512 moles .
hope this helps :)
Photosynthesis uses water and _____ _______ to produce sugar and oxygen.
Answer:
Photosynthesis uses water and Carbon Dioxide to produce sugar and oxygen.
Explanation:
During photosynthesis, plants take in carbon dioxide (CO2) and water (H2O) from the air and soil. Within the plant cell, the water is oxidized, meaning it loses electrons, while the carbon dioxide is reduced, meaning it gains electrons. This transforms the water into oxygen and the carbon dioxide into glucose.
PLS HELPPP!!!!!!!!!!!
Answer:
c
Explanation:
ionic bonds; cations (metals) GIVE electrons to anions (nonmetals)
When a wavelength (increases/decreases) the frequency (increases/decreases) and the energy (increases/decreases)
Answer:
As a wavelength increases in size, its frequency and energy (E) decrease. From these equations you may realize that as the frequency increases, the wavelength gets shorter. As the frequency decreases, the wavelength gets longer. There are two basic types of waves: mechanical and electromagnetic
Explanation:
hope it helps
plz mark it as brainlist
List 3 countries known to have poor water quality.
Answer
Ethiopia, Niger, Chad
Exlination-
What is the percent composition of carbon in the compound ?
Answer:
I'm pretty sure it's B
Explanation:
If i'm wrong i'm sorry :(