hope this help!
Obi is trying to determine if a powdery, solid substance is an element or a compound. After recording some observations, he strongly heats a sample of the solid over a burner flame. After fifteen minutes, he turns off the flame and allows the sample to cool. He records his final observations in the data table.
Which is the best explanation of his results?
The heating changed some of the sample to gas, causing the mass to decrease without breaking down the sample. Therefore, the original sample is a compound.
The appearance stayed the same, showing that the sample was not broken down by heating. Therefore, the original substance is an element.
The mass decreased during heating and some of the impurities escaped. Therefore, the original substance is an element.
The chemical reaction with acid changed, showing that the sample was broken down by heating. Therefore, the original substance is a compound
Answer: I am thinking C maybe.
Explanation: I don't if this is right but I think it is C.
Answer:
D
Explanation:
Took the test on edge...
what is the term for photosynthesis
What is the mass of 15 ml of aluminum if the density is 2.70 g/ml?
Answer:
40.5g
Explanation:
desnity = mass/volume
2.7 = mass/15
mass = 2.7 x 15
mass = 40.5 g
how many atoms does Mg(NO3)2 have thanks
Answer: Magnesium nitrate compound contains one atom for magnesium, two atoms for nitrogen, and six atoms for oxygen.
CREDIT safsaf
Help plsss!
If the average atomic mass is 39.948amu, which isotope is more abundant?
Answer:
It depends on which element you are talking about. I appears that no element has an average atomic mass of that number. So, for the question, if it assumes that there are two isomers with 39 amu and 40 amu, then the 40 amu one would be more abundant. But again, there are different possible isotopes and I can't tell what the question wants.
PLEASE HELP IM ON A TIME LIMIT!!!!
Which mathematical statement shows the relationship between gravity and mass?
F g ~d^/m
F g~m/d^2
F g ~ m/d
F g ~m^2/d
Answer:
The corect answer is F g~m/d^2
Explanation:
Answer:
F g~m/d^2
Explanation:
can you guys help me please? I dont get what im supposed to do here.
Pleaseee help ASAP
will mark brainliest!!! <3
Answer:
Fluorine belongs to the group 7 A so it must have 7 electrons in the oribits so the answer would be A as u count the electrons in the orbits, There are exactly 7 electron
Explanation:
A scientist is studying the liquid shown here. She thinks the liquid is a mixture. Describe an investigation she could do to demonstrate that the liquid is in fact a combination of substances.
( please help it’s due today lol! i will mark your answer as brainliest or whatever .)
Answer: Measure the density
Explanation: pretty sure the density could identify if it is a mixture or a pure substance
4. Which elements would have similar properties to potassium?
A. Lithium and Sodium
B. Bromine and Krypton
C. Calcium and Scandium
D. Cobalt and Rhodium
Answer:
The answer is A. Lithium and Sodium
How does the snake's skull allow it to eat large prey?
A. The jaw can crush the prey,
B. The teeth can grind the prey.
O C. The jaw can open wide around the prey.
D. The teeth can lock together around the prey,
Explain in your own words what chemical change is
Answer:
A chemical change happens when one chemical substance is transformed into one or more different substances, such as when iron becomes rust.
Explanation:
Answer: when one chemical substance is transformed into one or more different substances.
Explanation:
Zinc has an average atomic mass of 65.37 amu. Jack is trying to figure out what the most abundant isotope of zinc is, but he doesn't have access to the internet, so the average atomic mass is the only information he has. Jack decides to made an educated guess as to the most abundant isotope of zinc by assuming there are only two isotopes of zinc. If Jack assumes there are only two isotopes of Zn, what he be most likely to decide is zinc's most abundant isotope?
Question 5 options:
Zinc-64
Zinc-65
Zinc-68
Zinc-66
Zinc's most abundant isotope : Zinc-65
Further explanationIsotopes are atoms whose no-atom has the same number of protons while still having a different number of neutrons.
So Isotopes are elements that have the same Atomic Number (Proton)
Atomic mass is the average atomic mass of all its isotopes
In determining the mass of an atom, as a standard is the mass of 1 carbon-12 atom whose mass is 12 amu
Mass atom X = mass isotope 1 . % + mass isotope 2.%
To decide zinc's most abundant isotope, then choose the closest mass number
or we can check the difference with the average mass number, if the value is the smallest, then that isotope has the largest abundant
Zinc-64[tex]\tt \dfrac{65.37-64}{65.37}=0.021[/tex]
Zinc-65[tex]\tt \dfrac{65.37-65}{65.37}=0.005[/tex]
Zinc-68[tex]\tt \dfrac{68-65.37}{65.37}=0.04[/tex]
Zinc-66[tex]\tt \dfrac{66-65.37}{65.37}=0.009[/tex]
The closest = Zinc-65(the smallest)
Which situation describes the best example of rotational motion?
Craig sent the pool ball spinning toward the side pocket.
The skater repeated the figure eight on the ice.
Sara spun the dreidel on its pointed end.
The mouse ran in circles around the mousetrap.
Answer:
The actual Answer is :
C. Sara spun the dreidel on its pointed end.
Explanation:
there you go bruh brainliest pls
Answer: It’s C
Explanation:
It’s showing rotational motion duhhh :3
This element has 2 fewer protons than Titanium. What element is it?
Answer:
calcium.
Explanation:
because of
thanks
Describe the three phases of matter (solid, liquid, and gas) in terms of particle spacing, ability to fill shape and volume of container, energy of particles , and strength of intermolecular forces
Answer: solids are tense but spread out. Gas is spread out completely and liquid is all together
Explanation:
2. Mixtures can be solid, liquid or gas. It can be homogeneous or
heterogeneous and are made up of two or more components. Which of
the following mixtures where components are not visible??
Answer:
A solution is a special type of homogeneous mixture where the ratio of solute to solvent remains the same throughout the solution and the particles are not visible with the naked eye, even if homogenised with multiple sources.
Explanation:
Mixtures can be either homogeneous or heterogeneous': a mixture in which constituents are distributed uniformly is called homogeneous, such as salt in water, otherwise it is called heterogeneous, such as sand in water.
Compare and Contrast Heating and
Cooling curves.
Answer: Heating curves show how the temperature changes as a substance is heated up. Cooling curves are the opposite. They show how the temperature changes as a substance is cooled down. Just like heating curves, cooling curves have horizontal flat parts where the state changes from gas to liquid, or from liquid to solid.
Explanation: Have a blessed day hopefully this helped!
The inflation of airbags is due to the breakdown of a single chemical substance into two separate substances. Two molecules of sodium azide (NaN3) break down into sodium (Na) and nitrogen gas (N2) during the reaction. How many sodium (Na) atoms are produced in the reaction? 1 Na atom 2 Na atoms 3 Na atoms
Answer:
The correct answer is 2 Na atoms
Explanation:
To determine the number of sodium atoms produced in this reaction, the reaction described in the question must be written out in an equation and then balanced
2NaN₃ ⇒ 2Na + 3N₂
From the equation above, it can be deduced that the number of sodium atoms produced in the reaction described in the question is 2
Answer:
C) 2 Na atoms
Explanation:
Bill Nye said the air pressure makes things what?
PLEASE SOMEONE HELPP
Answer:
D
Explanation:
Which statement best describes how entrepreneurship affects a society's
economy?
A. It encourages people to take risks to create new products.
B. It organizes the people who help a business operate.
C. It provides the raw materials needed to produce goods.
D. It supplies businesses with the tools they need to function.
Answer:it’s a
Explanation:cause
Why does oil float and not sink?
Answer:
because it has more density than water
Answer:
This is because oil is less dense than water and therefore it floats to the surface.
What does it mean for an element to be oxidized?
A. The element is a spectator ion in a chemical reaction.
B. The element has gained one or more electrons in a reaction.
C. The element has lost one or more electrons in a reaction.
D. The element has bonded to another element with opposite charge
Answer:
B
Explanation:
Oxidation occurs when an atom molecule or ion loses one or more electrons in a chemical reaction when oxidation occurs the oxidation state of the chemical species increases oxidation doesn't necessarily involve oxygen originally the term was used when oxygen caused electron loss in a reaction hope this helped. :)
An element is oxidized when It has loses one or more electrons in a chemical reaction. Therefore, Option (C) is correct.
What is Oxidation ?The loss of electrons, gain of oxygen or loss of hydrogen will be considered as Oxidation.
The gain of electrons, loss of oxygen or gain or hydrogen will be considered as the Reduction.
Rusting is one of the popular example of oxidation.
Therefore, An element is said to be oxidized when It has lost one or more electrons in a reaction.
Hence , Option (C) is correct.
Learn more about Oxidation here ; https://brainly.com/question/16976470
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helpppp
Chemical bond formation might take place due to the interaction between a(n) _______ and an anion
A.magnetic
B.valence
C.electrostatic
D.cation
Billy is trying to figure out what type of wood to use for building a model boat. He has a block of wood with a volume of 8.0 cubic centimeters (cm3) and a mass of 4.0 grams (g). What is the density of the block of wood in g/cm3 to the nearest tenth?
A 0.5
B 2.0
C 4.0
D 32.0
Answer:
A; 0.5
Explanation:
To find the density, you have to do the Mass divided by the Volume; in this case, it's 8.0/4.0.
8/4 = 0.5
Which substances from the simulation are more alkaline than water?
Which
Answer:
The substances more alkaline than water are;
1) Spit, 2) Blood, 3) Hand Soap, and 4) Drain Cleaner
Explanation:
The diagram in the simulation displays a list of liquid substances, arranged from bottom to top in the order of increasing alkalinity.
The ph of water is 7.0
The ph of spit (saliva) is between 6.2 and 7.6
The ph of blood is about 7.4
The ph of hand soap is between 9 and 10
The ph of drain cleaner is between 12 and 14.
Which hypothesis is testable using a scientific experiment?
A. A fried egg is better than a hard-boiled egg.
B. Brown eggs are more attractive than white eggs.
C. Eggs with large yolks are more expensive than eggs with small
yolks.
D. You can boil an egg faster at high altitudes than at sea level.
what is chemistry about
Answer:
Explanation:
Chemistry is important because everything you do is chemistry! Even your body is made of chemicals. Chemical reactions occur when you breathe, eat, or just sit there reading. All matter is made of chemicals, so the importance of chemistry is that it's the study of everything.
Answer:
its the science that deals with the properties, composition, and structure of substances like elements and compounds, the transformations they undergo, and the energy that is released or absorbed during these processes
Which characteristic of a substance is considered a chemical property?
its boiling point
its reactivity
its density
its conductivity
Answer:
Reactivity
Explanation:
a chemical reacting to another chemical is considered a Chemical property because chemicals react with other chemicals differently. Pls PLs give me brainliest
Answer:
reactivity
Explanation: