Answer:
A
Explanation:
B,C,D is incorrect about atomic model
Last 2 pages out of 4 please help me with the others if you can't help me with this one.
filtering air to remove dust and pollen is it chemical or physical change
Answer:
Physical Change
Explanation:
Because the filter is removeing the dust by having the air go though a thin material.
Hope it helps!
Please answer correctly..
will give the brainliest!
Urgent!!!
a) lithium
Execution:
First, a magnesia stick is dipped in hydrochloric acid and then in lithium chloride. The stick is then held in the burner flame.
Observation:
The flame turns carmine.
b) ammonium ion
Execution:
Some ammonium sulfate is placed in a small vessel. A strip of indicator paper is moistened and stuck to the inside of a watch glass case. Then a few drops of hydrochloric acid are added to the ammonium sulfate and the watch glass bowl is held over the vapors that develop.
Observation:
The indicator paper turns blue because gaseous ammonia is produced, which reacts with the water in the indicator paper to form a base.
c) sulfate ions
Execution:
The ammonium sulfate is dissolved in water and treated with barium chloride solution.
Observation:
A white, poorly soluble precipitate of barium sulfate is formed.
d) presence of water
Execution:
Anhydrous copper sulfate, which is white, is added to the substance to be tested.
Observation:
In the presence of water, the salt turns light blue.
e) carbonate ions
Execution:
A few drops of hydrochloric acid are placed on the solid calcium carbonate.
Observation:
A gas evolution can be observed, during which carbon dioxide is produced.
f) iodide ions
Execution:
A potassium iodide solution is mixed with silver nitrate solution.
Observation:
A yellow precipitate of silver iodide is formed.
Calculate the density in grams per cubic centimeter of a material that has a mass of
720 milligrams and a volume of 10.0 cubic centimeters. =
Answer:
1.72 g/cm ^3
Explanation:
what is an atoms nucleus made of
Answer:
The nucleus is a collection of particles called protons, which are positively charged, and neutrons, which are electrically neutral. Protons and neutrons are in turn made up of particles called quarks. The chemical element of an atom is determined by the number of protons, or the atomic number, Z, of the nucleus.
are books on a table transparent ir opaque
Answer:
no
hope this helps
:)
Explanation:
a 100 gram sample of iron ore was found to contain 44g of iron. How many grams of iron are in a 450 gram sample of the ore?
Answer:
There are 198 grams of iron in a 450-gram sample of the ore.
Explanation:
From the given information:
Given that:
100-gram sample of iron ore is found in 44g of iron.
Thus. the grams of iron that can be found in a 450-gram sample of the iron ore can be computed as follows:
100g of iron ore = 44g of iron
450 gram of iron ore = x g of iron
x(g) of iron = ( 44g of iron × 450 gram of iron ore) / 100g of iron ore
x(g) of iron = 198 grams of iron
Thus, there are 198 grams of iron in a 450-gram sample of the ore.
Hydrogen can be found in many things. It cannot be broken down to create something else. An example of something like hydrogen is oxygen. We call things like hydrogen or oxygen _ .
Answer:
matter im pretty sure sorry if its wrong
Explanation:
based on the property of conserving matter, matter can not be created or destroyed
need help asap first comment gets brainiest answer
what is your impression of nuclear power
5. The prefox Semi-Deans Capardy SC Based on your knowledge of the properties of elements, which kind of elements is most likely to make semiconductors?
A supply of copper pipes is stored outdoors. Over the course of many years, the copper reacts with oxygen and turns green. What clue indicates a chemical reaction took place?
Answer: the oxidation of the copper (it turning green)
Explanation:
Mark all correct answers. Which of the following statements correctly describes plasmas
ANSWER Plasamas are good conductors of electricity and are affected bt magnetic fields
What is the relationship between the number of each atom used to form compound and oxidation number?
Answer:Explanation:
In compounds, all other atoms are assigned an oxidation number so that the sum of the oxidation numbers on all the atoms in the species equals the charge on the species.
3. A substance which is made up of two are more different
elements chemically combined is known as
A. an atom
B. a substance
C. a compound
D. a molecule
Answer:
Im pretty sure it c
Explanation:
For lunch you have a glass of sweetened ice tea. The glass contains crushed tea leaves, sugar, a slice of lemon, and both liquid and frozen water (ice cubes). Which of the following categories of matter best describes the contents of the glass? *
Answer:
I think solids
Explanation:
sorry if its not right
Soil is an important resource. The erosion of soil is a problem worldwide. Which human activity MOST directly increases soil erosion?
Group of answer choices
Answer:
Farming/agriculture
Hope this helps and have a great day :)
And please mark me brainliest if you can :)
Explain why the several different types of microscopes are all necessary.
Answer:
some zoom in farther
Explanation:
some microscopes zoom in farther than others so we can see even smaller things
is this correct? say something if it's wrong lol
Answer:
seFG9zuh98gufhIUAFIyhA*UGH8gguuguuuuuuuu
Explanation:
Answer:
Yes that look about right to me :)
Plz help! :) :D I will mark you as BRAINLIEST for the best answer!!! ( I actually mean it)
Physical and Chemical Properties of Magnesium
Here is an EXAMPLE of how it has to be like. Instead of Mercury, you HAVE to do Magnesium
Physical Properties of Mercury: ”I’m a highly stable element, so you can count on me”
Chemical Properties of Mercury: ”I love to travel but I do corrode aluminum so we won’t be flying off on adventures in airplanes planes anytime soon”
Single energy transformation
answer:
a change from one form of energy to another
explanation:
All the elements in the universe heavier than Helium are/were created _______.
a.
during the Big Bang
b.
by stars
c.
by chemical reactions
d.
from Lithium
Answer:
B. by stars
Hopes this helps
Explanation:
Which concept guided Mendeleev’s organization of the periodic table?
In a chemical reaction, atoms are not created nor destroyed.
All matter is composed of atoms.
Matter can be classified as a pure substance or mixture.
Properties of elements repeat in predictable patterns
Answer:
Properties of elements repeat in predictable patterns.
Question 3 (3 points)
(03.04LO)
Match the formula to the correct name. (3 points)
Column A
Column B
1.
Cas
a. Calcium sulfide
2.
CaSO4
b. Calcium sulfate
3.
CaSO3
C. Calcium sulfite
Answer:
Column A [tex]{}[/tex] Column B
1. CaS [tex]{}[/tex] Calcium Sulfide
2. CaSO₄ [tex]{}[/tex] Calcium sulfate
3. CaSO₃ [tex]{}[/tex] Calcium sulfite
Explanation:
1) Calcium sulfide is a compound formed between calcium, Ca, and sulfur, S, with a chemical formula of CaS. It forms cubic crystals similar to rock salt, and smells like rotten eggs
2) Calcium sulfate is a chemical compound consisting of calcium, Ca, and sulfate SO₄. It is found in nature in the hydrated form as the mineral gypsum
3)Calcium sulfite is a chemical compound formed between calcium, Ca and sulfite, SO₃ used to treat water and preserve food.
Answer:
the formula for calcium sulfite is CaSO3
the formula for calcium sulfate is CaSO4
the formula for calcium sulfide is CaS
Explanation:
6.82
A 2.10-mole sample of crystalline acetic acid, ini-
tially at 17.0°C, is allowed to melt at 17.0°C and is
then heated to 118.1°C (its normal boiling point) at
1.00 atm. The sample is allowed to vaporize at.
118.1°C and is then rapidly quenched to 17.0°C, so
that it recrystallizes. Calculate AH° for the total pro-
cess as described.
Answer:
0 kj
Explanation:
melting/initial temperature = 17.0°c
boiling point = 118.1°C
pressure = 1.00 atm
2.10 mole sample of crystalline
attached below is the detailed solution required
Two reasons photosynthesis is important
Answer:
Gives us oxygen to live, and if produces products such as, rubber, timber, herbs, and medicines.
Plz Help!
Make a funny sentence for flammability and compounds for Magnesium
what type of reaction is
CuO + H2SO4 ➡️ CuSO4 + H2O
What phenomenon does the Coriolis effect arise from?
Answer:
because our planet is spinning
which means the objects near the equator are moving at much faster velocities than objects at higher latitudes
I hope this helps✌
Be sure to answer all parts. Given that an E2 reaction proceeds with anti periplanar stereochemistry, draw the products of each elimination. The alkyl halides in (a) and (b) are diastereomers of each other. How are the products of these two reactions related? When drawing alkene substituents, remember that it is preferable to draw them as regular lines than as dashes and wedges. a. untitled draw structure ...
Answer:
hello your question is incomplete attached below is the complete question and answer
answer: attached below
Explanation:
A) attached below
B) attached below
