Answer:
4.5 + 2.34 = 6.8
Sig Figs:
2
Decimals:
1
Scientific Notation:
6.8 × 10ⁿ
Words:
six point eight
A hair gel is a mixture. Which of the following is true about hair gel?
A. A chemical change is required to separate its mixed components
B. A physical change can separate its mixed components.
C. It is made up of millions of units of a single type of compound.
D. It is made up of millions of atoms of a single element
Answer:
B. A physical change can separate its mixed components.
Explanation:
Atoms and molecules of different elements can come together to form a substance known as MIXTURE. A mixture comprises of several units of different elements or compounds that are not chemically joined together. This is the case of hair gel, which is a mixture i.e. it contains several compounds mixed together in an uneven ratio.
Since the components of a mixture such as the hair gel, are not joined together chemically i.e no chemical bonding or altering of chemical structure occurs between the mixture constituents, they can be separated using physical means. Physical methods of separation such as boiling, chromatography, etc.
Which factor causes a decrease in the rate of dissolution?
decreasing the amount of solute
increasing the stirring of the solution
decreasing the surface area of the solute
increasing the temperature of the solvent
Answer:
The correct option of the first option
Explanation:
Dissolution of a solute in a solution is the process in which the solute interacts with the solvent leading to the disappearance of the solute to form a solution. Rate of dissolution is primarily affected by three factors namely
Stirring of the solution: Stirring the solution causes the solute to interact more with the solvent, thus increasing the rate of dissolution.
Surface area of the solute: The smaller the surface area of the solute, the more easier it is for it (the solute) to interact with the solvent. Hence, the smaller the surface area, the faster the rate of dissolution.
Temperature of the solvent: An increase in temperature of the solvent causes the generally causes more things to dissolve in this solvent due to increased energy of molecules in the solvent, which causes the molecules of the solute and solvent to interact more.
A decrease in the amount of solute will reduce the amount of interaction the solute (since it is in lesser quantity) have with the solvent hence the rate of dissolution will also be low (even though a solution will still be formed).
There are different factors that influences chemical equations. The factor that causes a decrease in the rate of dissolution is decreasing the surface area of the solute.
Dissolution rate is simply known as the transfer rate of some specific drug molecules from the solid particles which is usually crystalline in nature into solution as self free drug molecules. The rate of Dissolution can be determined by the forces of the crystal.Surface area is known to affect the rate of dissolution. Note that When the total surface area of the solute particles is increased, the solute will then dissolves more quickly than ever.
The breaking of a solute into smaller pieces in turn do increases its surface area and increases its rate of solution and the act of stirring, do allows the solute to dissolve faster.
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If Thomson was asked about Dalton's Atomic Theory, what would he say? (2+ sentences)
"Through my own experiments, I have discovered the existence of a previously unknown subparticle-the electron. Because of this, Dalton's conclusion that atoms are indivisible particles is incorrect."
A metal ‘X’ has high melting point, good conductor of electricity, and is most malleable. Then the metal ‘X’ is A) Cu B) Au C) Fe D) Pt
Answer:
A) Cu
(copper)
HELP PLEASE!!!
what is the density of a cube that has the volume of 12mL and a mass of 6g? express in g/mL
Answer:
The density of the cube is 0.5g/mL. Hoped this helped! :)
Explanation:
V= 12.0mL D=M/V
M= 6.0g
D= 6.0g/12.0mL
D= 0.5g/mL
2. A block of wood has a mass of 360 grams and a density of 60 g/cm3. What is the volume
of the block of wood?
Answer:
6cm
Explanation:
The volume of the block of wood of 360 grams has been 60 ml or 60 [tex]\rm cm^3[/tex].
The density of an object can be defined as the mass of an object per unit volume. Density plays a pivotal role in the object sinks or floats into a liquid.
If the density of an object is lighter than the density of the liquid, the object will float onto the liquid. If the density of an object is more than the density of the liquid, the object will sink in the liquid.
Density can be given by:
Density = [tex]\rm \dfrac{mass}{volume}[/tex]
Mass of the object = 360 grams
Density = 60 g/[tex]\rm cm^3[/tex]
Volume = [tex]\rm \dfrac{mass}{density}[/tex]
Volume = [tex]\rm \dfrac{360}{60}[/tex]
Volume = 60 [tex]\rm cm^3[/tex] .
1 [tex]\rm cm^3[/tex] = 1 ml
Volume = 60 ml.
The volume of the block of wood of 360 grams has been 60 ml or 60 [tex]\rm cm^3[/tex].
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You and your friends were studying lists of spelling and vocabulary lists. It seemed like everyone could easily remember the first word on the list and the fifteenth word on the list. It seemed very hard to remember the words in the middle of the list. What is the hypothesis?
Answer:
you have a bad memory?
Explanation:
3. The water in a beaker has a mass of 200 g. An electric current is
tumed on in the water for two hours. Afterward the water has a
mass of only 176 g. What happened to the missing mass?
Answer:
Through electrolysis, some of the water became hydrogen gas and oxygen gas
Explanation:
I just took a test on this online.
The passage of current through water results in the formation of hydrogen gas and oxygen gas. This both will evolves out and the remaining water will have lessor mass than the initial.
What is electrolysis?Electrolysis is the process of conversion of electrical energy to chemical energy by applying an electric field. Electrolysis involves an electrolyte which can conduct by furnishing ions.
Generally electroanalytical cells involves two metallic electrodes which are immersed in a molten electrolyte containing the same metal ions.
When an electric current is passed through water, it will undergo electrolysis and produce hydrogen and oxygen in gaseous state. These gases bubbles out from the water and therefore, there occurs a mass loss for water.
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#SPJ2
Who discovered the flame test
Answer:
Thomas Melvill
Explanation:
...
A vial is filled with room temperature water, and blue cold water has been placed at the bottom. A warm water bag sits next to the vial. What do you think will happen?
Explanation:
In the context, a vial which is used in store medical samples is filled with water at room temperature. And the vial is kept on a cold water. Also a water bag containing warm water is kept near the vial.
The cold water kept at the bottom of the vial is having lower kinetic energy while warm water will have higher kinetic energy than the others. Since the water in the vial is at room temperature and it is in touch with the cold blue water, the water in the vial will loose or give its temperature to the cold blue water through conduction as well as convection process since temperature always flows from a hot body towards the cold body.
On the other hand, the warm water placed next tot he vial will give its temperature to the atmosphere.
what happens during covalent bonding?
Answer:
The atoms share some of their outer electrons so that each atom has a stable noble gas arrangement.
Explanation:
Neutrons have a
charge?
neutral
negative
positive
Answer:
Neutrons have a neutral charge
Explanation:
A neutron consists of 3 quarks, 1 up and 2 down. The up quark has a charge of + 2/3e, and the down quarks each have a charge of - 1/3e. So, the charges on the 3 quarks tend to cancel out to produce a neutrally charged particle.
When dealing with Atoms, what does MAN mean?
Answer:
when dealing with atoms man means man-made because man means man-made
If you had zinc and copper and melted it down into uranium what would happen? I will mark brainliest
Answer: Major radioactive elements (such as uranium) break down and create lead as one of ... Exposure to even small amounts of lead can be harmful since lead has no use in the body. ... of all industrial metals in the world because lead is easily re-melted and refined. ... Other metals that are found with zinc are silver and copper.
Explanation:
Match the scientist to his contribution to the atomic theory - Thomson - Rutherford - Bohr A. Electron energy levels B. Nucleus C. Electrons
Answer: Thomson - C
Rutherford - B
Bohr - A
Explanation: I just took the quiz
How do researchers select a sample that is representative of its population
Explanation:
Using stratified random sampling, researchers must identify characteristics, divide the population into strata, and proportionally choose individuals for the representative sample. ... For example, individuals who are too busy to participate will be under-represented in the representative sample.
who can answer question 7
What neutral element has the electron configuration described by the Aufbau diagram above.
Answer:
Aluminium.
Explanation:
The above electronic configuration can be written in a simplified form as shown below:
1s² 2s²2p⁶ 3s²3p¹
Next, we shall determine the number of electrons in the atom of the element as follow:
Number electron = 2 + 2 + 6 + 2 + 1
Number of electron = 13
Next, we shall determine the number of protons.
Since the element is in its neutral state,
The number of electrons and protons are equal i.e
Proton = Electron
Number of electron = 13
Proton = Electron = 13
Proton = 13
Next, we shall determine the atomic number of the element.
The atomic number of an element is simply the number of protons in the atom of the element i.e
Atomic number = proton number
Proton = 13
Atomic number = 13
Comparing the atomic number of the element with those in the periodic table, the element with the above electronic configuration is aluminium since no two elements have the same atomic number.
Which is classified as an inner transition element?
a) calcium
b) copper
c) fermium
d) helium
Suppose a mountain range is made up of 18 mountains, each mountain has
8800 trees on it, and each tree has 125,000 leaves on it.
How many leaves are
on all of the trees in the mountain range? Express your answer in scientific
notation.
The answer is 1.98 x 10^10 leaves.
18 mountains x 8800 trees = 158400 total trees
158400 total trees x 125000 leaves = 19800000000 total leaves in entire mountain range
Sci not: 1.98 x 10^10 leaves
To do scientific notation, put the decimal place right after the first digit in the number and count how many places are behind the decimal. you'll write the number of places after the decimal after the ^ in the 10^.
Thermal radiation emitted by objects allows us to feel infrared
energy as _____
Answer:
THERMAL IMAGING
We can sense some infrared energy as heat. Some objects are so hot they also emit visible light—such as a fire does. Other objects, such as humans, are not as hot and only emit only infrared waves.
(01.01 MC)
Which of the following could be considered a scientific statement
Answer:
hmmmm not sure and don't know
Explanation:
HELP PLS!!!!!!! NEED THIS IN 5 MINS
2. What kind of bond is pictured in the diagram to the left? Describe the movement of the valence electrons in the bond above? (Hint: Sharing or giving up?)
in a complete sentence pls
Answer:
Sharing or covalent bonding is taking place.
Explanation:
The valence electron will be shared by both the atoms so that means that the election will move around both of the atoms.
Convert 30°C into kelvin
Answer:303.15
Explanation:
The loops in Ptolemy’s model, and those shown on the video, are called motion. This phenomenon is caused by Earth’s orbit than those of other planets.
Answer:
The loops in Ptolemy’s ✔ geocentric model, and those shown on the video, are called
✔ retrograde motion. This phenomenon is caused by Earth’s
✔ faster orbit than those of other planets.
Explanation:
Answer:
✔ geocentric
✔ retrograde
✔ faster
Explanation:
The density of aluminum is 2.70 g/cm'. If the volume of a piece of aluminum is 90.4 cm', what is
the mass of the aluminum?
Answer:
33.4814814815
Explanation:
90.4/2.70
Suppose 10 atoms of carbon (C) react with 20 atoms of oxygen (O). According to the Law of Conservation of Matter, how many atoms will there be in the product of this reaction?(1 point)
A) 20
B) 15
C) 10
D) 30
Answer:
D 30
Explanation:
whenever there is a reaction, the amount of atoms don't change, because matter can't be created or destroyed. Add the carbon and oxygen atoms together
According to the Law of Conservation of Matter, there will be 30 atoms of product in the reaction.
LAW OF CONSERVATION OF MATTER:
The law of conservation of matter states that matter can neither be created nor produced in a chemical reaction. This further means that the amount of matter in the reactant of a reaction must equate that of the products. Hence, if 10 atoms of carbon (C) react with 20 atoms of oxygen (O), there will be 10 + 20 = 30 atoms of product in this reaction. Therefore, According to the Law of Conservation of Matter, there will be 30 atoms of product in the reaction.Learn more: https://brainly.com/question/24996173?referrer=searchResults
If you burn a piece of wood, it becomes a different substance. What type of
property is this?
A. Electrical property
O
B. Chemical property
C. Physical property
D. Mechanical property
Answer:
B. Chemical property
Explanation:
Answer:
B
Explanation:
a reaction has taken place in which you can't get back what you started with
What volume is equivalent to 14,000 mm cubed
Answer:
14mL
Explanation:
1mL = 1cm^3, 1000mm^3 = 1000cm^3
¿por qué entre el calcio (Ca) que pertenece al segundo grupo y el galio (Ga) que pertenece al tercer grupo hay 10 elementos, ¿Que nombre reciben estos elementos?
Answer:
Estos elementos se denominan metales de transición, metales pesados, elementos del bloque D, etc.
Explanation:
Aquí, en esta pregunta, queremos saber la razón por la cual hay un espacio de 10 elementos entre el calcio, que es un elemento del grupo dos, y el galio, que es un elemento del grupo 3.
Al observar la tabla periódica, la tabla periódica moderna, notamos un bloque de elementos entre los elementos del grupo 2 y los elementos del grupo 3 en la tabla periódica.
Entonces, ¿por qué se colocan estos elementos entre ambos grupos? Se colocan aquí porque no pertenecen en su totalidad al grupo 2, ni tampoco al grupo 3.
Estos elementos presentan una especie de estados de oxidación variables que son responsables de una amplia variedad de propiedades comunes entre ellos.