Answer
The answer is SOLIDS
Explanation:
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 mass of an atom if it has 11 protons, 12 neutrons, and 11 electrons
A,22, B.23, C34, D 11
Answer:
23, B
Explanation:
The mass of an atom is determined by the number of Protons + Neutrons. Here, if we assume the units is AMU (Which means the mass unit for a proton and neutron would be basically 1), the answer would be 11 + 12 = 23 AMU, which is B.
Answer:
B) 23
Explanation:
Relative Mass = number of protons + number of neutrons
Relative Mass = 11 + 12
Relative Mass = 23
How long does one complete orbit of Earth around
the sun take, give the amount in years and days?
Answer:365 days, 5 hours, 59 minutes and 16 seconds.
which two formulas represent compounds?
A.NaCI
B.HCI
C.H2
D.Ag
Answer: A and B
Explanation: A and b are Sodium chloride and Hydrogen chloride which are both compounds.
Answer: A. NaCI
Explanation: APEX
How many bromine atoms are present in 38.7 g of CH2Br2
Number of Br atoms : 2.679 x 10²³
Further explanationThe mole is the number of particles contained in a substance
1 mol = 6.02.10²³
Moles can also be determined from the amount of substance mass and its molar mass
[tex]\tt mol=\dfrac{mass}{MW}[/tex]
Proust stated the Comparative Law that compounds are formed from elements with the same Mass Comparison so that the compound has a fixed composition of elements
mass of Br in CH₂Br₂[tex]\tt mass~Br=\dfrac{2.Ar~Br}{MW~CH_2Br_2}\times mass~CH_2Br_2\\\\mass~Br=\dfrac{2.80}{174}\times 38.7=35.59~g[/tex]
mol of Br[tex]\tt \dfrac{35.59}{80}=0.445[/tex]
number of atoms[tex]\tt 0.445\times 6.02\times 10^{23}=\boxed{\bold{2.679\times 10^{23}}}[/tex]
A piece of aluminum has a mass of 12.0 g. When it is placed into a graduated
cylinder with 14.0 mL of water, the water level rises to 18.5 mL. What is the density
of aluminum?
0 2.66667g/ml
O 2.67 g/mL
O 2.667g/mL
O 2.7 g/mL
Answer:
The answer is 2.7 g/mLExplanation:
The density of a substance can be found by using the formula
[tex]density = \frac{mass}{volume} \\[/tex]
From the question
mass = 12 g
volume = final volume of water - initial volume of water
volume = 18.5 - 14 = 4.5 mL
So we have
[tex]density = \frac{12}{4.5} \\ = 2.66666666...[/tex]
We have the final answer as
2.70 g/mLHope this helps you
Why were enslaved Africans in high demand in the southern colonies?
Answer:
Slaves were in high demand in the southern colonies because they were the main source of labor. ... Bacon and others colonists wanted to take the Natives land.
Explanation:
HOPE THIS HELPED ❤✨
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,
What all indicates a CHEMICAL change? *
A Solid melting into a liquid
After the change the substance is still reactive with oxygen
One substance becomes two new substances
The melting point was 100 deg C but after the change the melting point was 256 deg
C.
one substance becomes two new substances
What strategy should be done to provide quality education without discrimination?
Explanation:
The Committee has already adopted general comment No. ... Non-discrimination - education must be accessible to all, especially the most ... developmental strategy for its school system.as poverty and discrimination and to provide education of sufficient quality, in a manner that ensures children can benefit from it.
If I walk 10 meters down the hallway, then 2 meters into a classroom, what is my total distance walked in meters(write the number)
Answer:
12 meters
Explanation:
If you were to decrease thermal energy, what would happen to the particles?
Answer: Explanation:
You can change an object's state of matter by adding or removing thermal energy. When you add thermal energy to an object, these things can happen: Particles move faster (increased kinetic energy). Particles get farther apart (increased potential energy).
Human body uses the energy provided from food digestion. Endothermic or exothermic?
Answer:
Endothermic
Explanation:
Exo is outside so exothermic would be outside the body
The carbohydrates are break down into glucose. Then glucose combines with oxygen in the cells and provides energy. Hence, digestion is an exothermic process.
What is an exothermic process ?Food digestion produces heat. This happens as a result of the organism releasing heat during meal digestion. A process that releases heat is exothermic.
Heat is released during an exothermic reaction, raising the temperature of the immediate environment. The environment is cooled through an endothermic process that absorbs heat.
Glucose is created by the breakdown of these carbs. In the cells of our body, this glucose interacts with oxygen to produce energy. So, the process of digesting is exothermic.
Chemical processes involved in food digestion disassemble large food molecules into smaller, more manageable "building block" components.
Thus, Human body uses the energy provided from food digestion is exothermic process.
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can anybody help me? ill mark brainliest!!! please ITS TIMED
Density = Mass/Volume but it can also be rearranged to:
Mass = Volume x Density
Given in the question:
Volume - 44.9 cc
Density - 19.3 g/cc
Calculation
Mass = Volume x Density
= 44.9 x 19.3
= 866.57 g
The mass of an atom Is found by adding Its protons and .The electric charge of an atom Is found by adding the charges carried by Its protons and .
Answer: the 1st answer is neutrons and i think the 2nd is nucleus
Explanation:
The mass of an atom is found by adding its protons and neutrons. The electric charge of an atom is found by adding the charges of its protons and electrons.
What is atomic mass?The atomic mass of an element is the total number of protons and the number of neutrons carried by one atom of that element. The atomic mass of an element is usually expressed in grams or a.m.u.
The atomic mass of an element = No. of protons + No. of neutrons
or
The atomic mass of an element = No. of electrons + No. of neutrons
The atomic number gives us information about how many protons are inside the nucleus of the atom. Elements are recognized by the number of protons in the nucleus. Neutrons are uncharged elementary or subatomic particles that are stable when bound in an atomic nucleus.
As the electrons and protons are charged particles in an atom, therefore, the sum of the charge carried by them is equal to the electrical charge of the atom.
For a neutral atom, the number of protons present in an atom is always equal to the number of electrons.
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ANSWER FAST PLEASE!!
Which is a true statement about a zero net force?
A zero net force causes a change to an object’s direction.
B.zero net force causes a change to an object’s speed.
C.A zero net force causes a change to an object’s acceleration.
D.A zero net force causes no change in an objects motion.
Answer:
D)a zero net force causes no change in an objects motion.
A zero net force causes no change in an object's motion. This statement is true about zero net force. Therefore, option D is correct.
What is zero net force ?An item that is originally at rest and has no net forces operating on it will stay at rest. If it is going, it will keep moving straight forward at a consistent speed. Forces are "pushes" or "pulls" on the object, and they are vector numbers, just like acceleration and velocity.
A automobile travelling at 50 mph on a highway continually has a net force of zero even though it is moving, since there is no acceleration and the speed is constant.
The total net force acting on an object as it moves at a steady speed is always zero. If you apply force, friction or another force (or several forces) will balance it out.
Thus, option D is correct.
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Complete the sentence.
Atoms form chemical bonds to satisfy the
rule and to become
Answer:
Whats the sentence
Explanation:
Answer:
Atoms form chemical bonds to satisfy the octet rule and to become stable.
Got it right on Edg. 2020, hope this helps!
The number of protons in an element can be found by looking at the
symbol
atomic number
O average atomic mass
O name
Answer:
atomic number if it's a answer
Answer:
I think its the average atomic mass.
Explanation:
Question 1 (4 points)
Which of the following is/are true about Van der Waals forces?
A. They are very weak
B. They are a a type of momentary dipole
C. Both 1 and 2 are correct
D. neither 1 nor 2 is correct
Answer:
C. Both 1 and 2 are correct.
Plz help! This question is due in 10 mins!
Calculate the density of a 5cm3 cube of iron with a mass of 100 g
Answer: 20
Explanation: I’m in your class.
If all the deer disappeared from this community, which change would be most
likely to occur?
Answer:
i think the grass population would decrease
Explanation:
Answer:
The Coyote population would decrease
Explanation:
the sum of all the kinetic energies of an object is it's
Answer:
The sum of potential energy and macroscopic kinetic energy is called mechanical energy and stays constant for a system when there are only conservative forces (no non-conservative forces). The more mass a moving object has, the more kinetic energy it will possess at the same speed.
Explanation:
Answer: Mechanical energy
Explanation: The more mass a moving object has, the more kinetic energy it will possess at the same speed
What is the most important scientific process
Answer:
atoms bonding
Explanation:
How many protons are there in a neutral, stable Hydrogen atom that makes up 99.985% of the element?
A. 1
B.2
C.3
D.4
E.0
What is the proof of the chemical reaction?
Answer: The chemical is disrupted, also most likely causing an explosion.
Explanation:
!!!WILL GIVE YOU BRANLIEST!!!!
which option is an example of a physical change??
A breaking chemical bonds
B forming chemical bonds
C nuclear decay
D melting a substance
which option is an example of a chemical change
A ironing a shirt
B melting cheese
C grinding powder
D fireworks exploding
Answer:
D
Explanation:
Melting of ice is a physical change as there no new compound is forming only state is changing So Option D is correct option. For second question Option D is correct option as combustion reaction is taking place.
What is chemical change?Chemical change is a reaction in which breaking and forming of new bonds take place. One molecule completely converted to totally different molecule. The number of atoms remains same
One famous example of chemical change is the rusting of iron. The color, odor and arrangements of atoms in products are very much different from reactant. Chemical change are mostly irreversible in nature. Physical change is just opposite of chemical change. Phase change is an example of physical change.
Thus option D is correct option in both cases.
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Can somebody please help me with this ASAP!
Convert this mass to SI Unit: 2000g
Answer: 2 kg
Explanation:
Is hydrogen a metal or a nonmetal? How many valence electrons does a hydrogen atom have?
Answer:
hydrogen is a non-metal, and has one valence electron.
Explanation:
Hope this helps!!
Hydrogen shows properties of both metals and nonmetals. However, hydrogen is placed with the alkali metals since it contains one valence electrons.
What is hydrogen ?Hydrogen is the first element in the periodic table. It has only one electron and it is the valence electron of hydrogen. Therefore, hydrogen is placed in the first group of periodic table.
Hydrogen needs one more electrons to become stable. The 17th group elements halogens also have a valency of one. Hence, hydrogen shows some chemical similarities with halogens also.
Mostly hydrogen forms covalent bonds like non-metals and in rare cases, hydrogen forms ionic bonds by donating its electron. Therefore, hydrogen is mostly considered as a non-metal.
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Why is it important for you to know the properties and chemical formulas of molecular and ionic compounds? How will this affect your ability to choose one product over another or make decisions about whether to use a certain substance like bleach or drain cleaner? How has learning about atomic structure and compounds changed your understanding of the world around you?
Answer:
See explanation
Explanation:
It is important to know the properties and chemical formulas of ionic and molecular compounds because, knowledge of the properties of a compound aids you in deciding how to use the compound, how to store it and how dangerous it can be. Knowledge of its formula is the first step towards identifying its properties since most chemicals occur in groups having similar chemical/physical properties.
Knowledge of the chemical properties and formula of bleach and drain cleaner will help you to decide which product is a better cleaning agent based on its chemical composition. This will help you as the user to make better decision.
Learning about atomic structure has made me to understand that all matter in the universe are composed of atoms. indeed, certain occurrences in nature can only be explained on the basis of atoms involved.