Answer:
Ways to reduce friction are by using oil, rollers from roller blades or other stuff that has a roller in or on it, wax, and grease.
Explanation:
Oil can reduce friction because it is used as a lubricant to reduce friction so moving surfaces slide smoothly over one another the same thing with wax and grease. The rollers are because they reduce friction by reducing contact between moving surfaces.
What is the molecular formula of a substance whose molar mass is 166.8 grams and its empirical formula is C2H4N2?
Answer:
C4H2O6
Explanation:
By using prefixes, we can write 32 × 10-10 kg as
Answer:
3.2 micro gram
Explanation:
because
1kg=1000g
32×10^-10kg=?
=3.2×10^-6g
1g=10^-6micro gram
3.2×10^-6g=?
=3.2 micro gram.
where g- gram
kg- kilogram
what is the energy source that powers plate movement?
A magma and lava
B Earth's magnetic field
C the sun
D Earth's hot interior
Answer:
D Earth's hot interior
Explanation:
The internal heat engine of the earth is the energy source that powers plate movement.
The sun drives the surface process and provides energy for the external heat engine
The earth's interior sources it heat from: decays of radioactive isotopesremnant heat from the formation of the earthfrictional heating from the movement of the earthTherefore, the heat is used to melt rocks and set up convection currents that drives plate movements.
Plz i wanna those answers click on the photo to see all the question they are 2 queastions part A and B
Answer:
a.
Turn paper Blue - these are alkaline/ base substances.
ToothpasteSoapBleachTurn paper Red - these substances are acidic in nature.
Lemon JuiceVinegarCola drinkb. i. A wasp sting - Lemon juice
ii. A bee sting - Toothpaste
iii. A wasp sting is alkaline which means that running an acidic substance like lemon or lemon juice on it should neutralize it.
A bee sting is acidic so an alkaline substance such as toothpaste should neutralize it as well.
When magnesium is heated in air, the product formed is heavier than the original ribbon. On the other hand when potassium magnate (7) is heated in air, the product formed is light. Explain the different observation
Answer:
See the answer below
Explanation:
When magnesium is heated in air, the element combines with oxygen to form a compound known as magnesium oxide according to the following equation:
[tex]2Mg(s) + O_2 (g)--> 2MgO (s)[/tex]
Hence, the product formed - a combination of magnesium and the oxygen component of air - is heavier than the original magnesium ribbon.
On the other hand, potassium manganate (7) is heated in air and decompose to form potassium manganate (6), manganate oxide, and oxygen gas according to the following equation:
[tex]2KMnO_4 --> K_2MnO_4 + MnO_2 + O_2[/tex]
Hence, the final product formed is lighter than the original product because oxygen gas has been evolved.
Answer:
During the heating of magnesium in air, it gains mass with the addition of oxygen present in air to form the oxide. However, during the heating of potassium manganate (vii), it decomposes or breaks down to simpler products and oxygen gas is given off.
Explanation:
During the heating of magnesium in air, it gains mass with the addition of oxygen present in air to form the oxide.
The equation for the reaction is given below:
2Mg(s) + O2(g) ---> 2Mg0
The molar mass of the magnesium metal is 24.0 g while the mass of the magnesium oxide is 40.0 g. The total mass of the metal before heating is 24 × 2. + 32 = 48.0 g. The total mass after heating = 48 + 32 = 80.0 g. Therefore, there is an increase in mass.
However, during the heating of potassium manganate (vii), it decomposes or breaks down to simpler products and oxygen gas is given off. The equation for the reaction is given below;
2KMnO4(s) ----> K2MnO4(s) + MnO2(s) + O2(g)
With the evolution of oxygen gas, there's a loss in mass of potassium manganate (vii). Molar mass of KMnO4 is 158.0 g while the mass of K2MnO4 is 197.0 g and that of MnO2 is 87.0 g. The total mass on the right hand side is 2 × 158 = 316.0 g. The total mass on the left-hand side with the exception of the gas evolved is 284.0 g. Therefore, there is a loss in mass.
if it were a very hot day , how would the speed at which we smelled the perfume change ? what about a very cold day ? why ?
Explanation:
On a hot day, the speed at which we perceived the smell of the perfume will be much faster due to the increase in kinetic energy of the perfume molecules.
Based on the kinetic molecular theory of gases, the average motion of particles increases as their thermal energy increases. On a hot day, the heat causes an increase in the average kinetic energy of the particles and the perfume molecules moves faster.
On a cold day, the molecules are slower and the rate at which we perceive the perfume smell is very slow. The particles will diffuse less faster and this is due to the low average kinetic energy they possess.
How is Zinc chloride formed in the lab and please tell the steps
Answer:
When zinc metal is reacted with hydrochloric acid, hydrogen gas is released and an aqueous solution of zinc chloride is produced. ... It is important that all of the zinc used be reacted and that large excess amounts of hydrochloric acid not be used.
Anhydrous zinc chloride is synthesized by treating zinc with hydrogen chloride. Whereas, hydrated and aqueous forms of zinc chloride are prepared by treating zinc with hydrochloric acid. Zinc metal could either be in the form of zinc sulfide or zinc oxide
Have a nice Day , Hope this helped you I would appreciate it if you could mark my answer brainliest
Merry Christmas
Answer: Anhydrous zinc chloride is synthesized by treating zinc with hydrogen chloride. ... Zinc metal could either be in the form of zinc sulfide or zinc oxide. ZnS(s) + 2 HCl(aq) → ZnCl2(aq) + H2S(g) There are impurities present in zinc chloride samples due to hydrolysis.
got this from goo.gle
Hope this helps.......... Stay safe and have a Merry Christmas!!!!! :D
Scientists are always learning new things. Which of the following shows how
scientists use observations to gain new understanding about the world?
A. Scientists have discovered new planets orbiting a star by
detecting a wobble in the star's motion.
B. Scientists hope to learn more about how many stars are in space.
C. Scientists wonder if other planets can support life, and some
scientists wonder if there are aliens.
D. Scientists are familiar with some galaxies, but they do not know
how many galaxies exist.
Answer:
The answer is B
How many joules must be added to a 1000 g iron skillet to increase its temperature
from 25°C to 250°C? The specific heat of iron is 0.449 J/gºC.
A) 449 J
B) 101,025 J
C) 50,000 J
D) 112,250 J
Answer:
B) 101,025
Explanation:
1000g * 0.449 J/g Celsius * 225 Celsius = 101,025
I got 225C from 250C - 25C
Consider the reaction H2O(g)+Cl2O(g)=2HClO(g). At equilibrium,the concentrations of the different species:[H2O]=0.077M,[Cl2O]=0.077M,[HClO]=0.023M. What is the equilibrium constant for the reaction at this temperature?
Choices: 0.089, 0.26, 3.9, or 11
The equilibrium constant K : 0.089
Further explanationGiven
Reaction
H₂O(g)+Cl₂O(g)⇔2HClO(g)
[H2O]=0.077M,[Cl2O]=0.077M,[HClO]=0.023M
Required
the equilibrium constant
Solution
The equilibrium constant or Kc is the value of the concentration product in the equilibrium state of the substance in the right segment divided by the product of the substance in the left section, each of which has a reaction coefficient raised
[tex]\tt K=\dfrac{[HClO]^2}{[H_2O][Cl_2O]}\\\\K=\dfrac{0.023^2}{0.077\times 0.077}\\\\K=0.08922[/tex]
A. 207 kJ
B. 4730 kJ
O C. 9460 kJ
O D. 414 kJ
Answer:
C = 9460 Kj
Explanation:
Given data:
Mass of copper = 2kg
Latent heat of vaporization = 4730 Kj/Kg
Energy required to vaporize 2kg copper = ?
Solution:
Equation
Q= mLvap
by putting values,
Q= 2kg × 4730 Kj/Kg
Q = 9460 Kj
Two balls of equal size are dropped from the same height from the roof of a building. One ball has twice the mass of the other. When the balls reach the ground, how do the kinetic energies of the two balls compare?
A. The lighter ball has more kinetic energy than the heavier ball because it had mass.
B. The heavier ball has more kinetic energy than the lighter ball because it has more mass
C. Both balls have the same kinetic energy because they were dropped from the same height.
Answer:
b the heavier ball has more kinetic energy than the lighter ball because it has more mass
Models are used to show which qualities of a compound’s chemical structure? a. bond angles c. bond length b. element color d. both a and c
Answer:
a. bond angles c. bond length
Explanation:
Models are abstractions of the real world. They are used to present either real or hypothetical situations either visually, graphically or through mathematical expressions.
In chemistry, to show bond angles and bond lengths, different models are used. One of such is the VESPR - valence shell electron pair repulsion- theory which the model upon which the bond relationships between elements in a compound is shown. Also, the hybridization schemes are excellent models for showing bond relationships.PLEASE HELP! DUE in 5 minutes
Answer:
Fluorine-18
Explanation:
An isotope is an element with different amounts of neutrons. The element itself will not change.
Help ASAP ......begdhzhshs
Answer:
thunderstorms
Explanation:
Will give brainliest
What type of bond is formed between atoms of a molecule of the product of this reaction? How can you determine which type of bond is formed between these atoms?
2 H2(g) + O2(g)⇒ 2 H2O(l)
Answer:
Explanation:
A decomposition reaction occurs when one reactant breaks down into two or more products. This can be represented by the general equation: AB → A + B. Examples of decomposition reactions include the breakdown of hydrogen peroxide to water and oxygen, and the breakdown of water to hydrogen and oxygen.
Answer:
Covalent bond
Explanation: Hydrogen and Oxygen are both non-metals, with a low difference in electronegativity. They will share electrons.
Which form of erosion would be the slowest?
Answer:
wind is the correct answer
One atom of element A bonds with element E.
Answer:
Ae4
Explanation:
which virtually showed the reaction between group 4 element and group 7 element
1. In a Stock system name such as iron(III) sulfate, the Roman numeral tells us (a) how many atoms of Fe are in one formula unit. (b) how many sulfate ions can be attached to the iron atom. (c) the charge on each Fe ion. (d) the total positive charge of the formula unit. 2. Changing a subscript in a correctly written chemical formula (a) changes the number of moles represented by the formula. (b) changes the charges on the other ions in the compound. (c) changes the formula so that it no longer represents the compound it previously represented. (d) has no effect on the formula.
Answer:
See explanation
Explanation:
1) The formula of the compound is Fe2(SO4)3. There are two ion atoms in any formula unit as we can see here. Three sulphate ions are attached to iron. Each iron ion carries a +3 charge as we saw in the formula. The total positive charge in each formula unit is +6.
Changing a subscript in a correctly written chemical formula changes the formula so that it no longer represents the compound it previously represented. Hence FeSO4 is a different compound from Fe2(SO4)3.
Minerals from water pass through the mold and over time the minerals fill that mold and it then becomes a cast in the same shape of the body of the animal that died?
True
False
The pH scale measures ___.
A. The concentration of hydrogen ions
B. The strength of solutions from 1 to 12
C. The concentration of bases
D. The concentration of acids
Answer:
a
Explanation:
it is the concentration of the hydrogen ion, more hydrogen ion more acidic less hydrogen ion less acidic and alkaline.
find the mass of electron
Answer: mass of electron is
9.10938356 × 10^-31 kilograms
Explanation:
Naturally occurring rubidium consists of just two isotopes. One of the isotopes consists of atoms having a mass of 84.912 amu; the other of 86.901 amu. What is the percent natural abundance of the heavier isotope
Answer:
The percent natural abundance is 27.95% for the heavier isotope (86.901 amu)
Explanation:
The atomic mass of Rubidium (Rb) is 85.468.
To find the percent natural abundance, first we need to use the following equation:
84.912x + 86.901(1-x) = 85.468
x represents the percent natural abundance, in basic decimal form
In order to find x, we will use the distributive property, combine like terms and then move the constant to the other side to get x.
We are first finding the percent natural abundance of the first isotope to make this easier for us.
84.912x + 86.901(1-x) = 85.468
-> 84.912x + 86.901- 86.901x = 85.468
-> 86.901 - 1.989x = 85.458 (like terms were combined)
-> Subtract both sides by 86.901
-> Divide both sides by-1.989x
x = 0.720462544
Now turn this into a percent by multiplying by 100.
--> 72.05% for the first isotope (the one that contains 84.912 amu)
To find the natural abundance of the other isotope (the denser, heavier isotope), you could just subtract 72.05 from 100 to save time, but the usually desired way (the way that your teacher would probably want you to do) is down below:
We plug this decimal for the x-value into the parentheses from earlier:
(1 -x) ---> ( 1 - 0.720462544 ) = 0.279537456
Now we just need to convert this to a percent by multiplying by 100
0.279537456 * 100 = 27.95% of the heavier isotope (86.901 amu)
what has 16 protons and -2 charge? PLEASE NEED IT FOR FINALS FOR CHEMISTRY!!
Answer:
Sulfur
Explanation:
it has 16 proton and 2- charges
In an exothermic reaction, the energy stored in the chemical bonds of the reactants is: (A) less than the energy stored in the bonds of the products. (B) equal to the total amount of energy released. (C) equal to the energy stored in the bonds of the products. (D) greater than the energy stored in the bonds of the products. My teacher told me it was A because of the idea with energy in - energy out. But when I searched it up, it was explained to be D. Which one is right?
Answer:
(D) greater than the energy stored in the bonds of the products.
Explanation:
Exothermic reaction refer to those reactions in which energy is released to the surrounding, unlike endothermic reactions where energy is absorbed from the surroundings.
In exothermic reactions, the change in energy; ΔH less than zero. That is, they are negative.
ΔH = H (products) - H (reactants)
For ΔH to have a negative value, it means the energy of reactant must be greater than the energy of products.
This means the correct option is;
(D) greater than the energy stored in the bonds of the products.
In an exothermic reaction the energy of the reactants bonds has been higher than the energy of the product bonds. Thus, option D is correct.
The exothermic reaction has been given as the chemical reaction in which there has been the liberation of energy by the reactants in the process of formation of products.
The energy change in the reaction has been a negative value. In the process of product formation, the energy of the system has been conserved. It stated that the energy of the reactant has been equivalent to the energy of the product and the liberated energy.
With the product being consisted of less energy, the energy stored by the chemical bonds in the reactants has been higher than the energy stored by the product. Thus, option D is correct.
For more information about the exothermic reaction, refer to the link:
https://brainly.com/question/14969584
help me pleaseeee, if you do tyy :)
in one molecule we have one oxygen atom so we will have 4 oxygen atoms in 4 molecules
How much mass does 1 mol of O2 gas have?
A.15.99 x2g
B. 15.99g
C. 2x (6.02x10^23)g
D.15.99 x (6.02x10^23)g
Answer:
D
Explanation:
We already know oxygen's mass is 15.99 amu, and the mass of a mole is 6.02 * 10^23, so just multiply the two together for 15.99 * (6.02 * 10^23) g.
15.99 x (6.02x[tex]10^{23}[/tex])g mass does 1 mol of O2 gas have. Hence, option D is correct.
What are moles?A mole is defined as 6.02214076 × [tex]10^{23}[/tex]of some chemical unit, be it atoms, molecules, ions, or others. The mole is a convenient unit to use because of the great number of atoms, molecules, or others in any substance.
We already know oxygen's mass is 15.99 amu, and the mass of a mole is 6.02 x [tex]10^{23}[/tex], so just multiply the two together for 15.99 x (6.02x[tex]10^{23}[/tex])g.
Hence, option D is correct.
Learn more about moles here:
https://brainly.com/question/8455949
#SPJ1
I just gotta say something right here. Because instead of looking for love, I'm learning to love myself and build a better relationship with God. I'm trusting God's timing, Ik he'll send me the man of my dreams, I'm waiting patiently. Just say this to ya self out loud and go on Pinterest for some quotes.
Answer:
ok thats cool good luck with that and always remember God is there for you :)
Answer:
yeah
Explanation:
in every situation we should trust God
To increase crop production, food engineers combine two plants so that each
plant's strength compensates for the other's weakness. What is this
technique called?
A. Gene alteration
B. Chemical alteration
C. Crossbreeding
D. Composite materials
Answer:
C.
Explanation:
Crossbreeding is the correct answer.
Answer:
C. Crossbreeding
Explanation:
Plz answer the question
Answer:
Equation:
p + 8p = 63
9p = 63
Divide both sides by 9:
p = 7
The parakeet weights 7 ounces.
Weight of fish:
The fish weights 8 times as much as the parakeet, or 8 * 7 = 56 ounces
The fish weights 56 ounces.
Explanation: