it's B
Explanation:
just because 1111111111111111111
Why is the reactivity of metal increase but that of non-metal decreases as we go down in a group of periodic table? (pls its important i need this question's ans for my exam so answer it fast thank you)
Answer:
Nonmetal reactivity decreases down a group because the nucleus' ability to gain more valence electrons weakens due to more nuclear shielding. For Metals: the most reactive metals are those that can lose their valence electrons the most easily. ... Francium is the most reactive metal
Explanation:
Answer:
While moving from top to bottom in a group of the periodic table, the reactivity of non- metals decreases. ... Thus, the tendency of gaining electron/s in the valence shell decreases as well as the chemical reactivity also decreases on moving from top to bottom in a group of non- metals.
Julio eats a taco for dinner. What represents a physical change in the taco?
A) saliva changing the starch in the crust to sugar
B) teeth tearing off a bite of a taco
C) chemicals in the stomach digesting proteins
D) breaking down of fats in the taco by bile
The physical change is a modification in the structure of the chemical substance. Teeth tearing off a bite of a taco represents a physical change. Thus, option B is correct.
What is a physical change?A physical change is an alteration in the structure of the chemical involved in the substance. In a physical change, the composition of the chemical remains intact and does not change. It includes changes in texture, temperature, shape, and phase of matter.
The processes like dissolving, boiling, cutting, melting, bending, and freezing are said to be physical changes. The teeth-bitting tacos result in smaller bites is a physical change as there is a change in the shape and size but not the composition.
Therefore, option B. the teeth tearing tacos is an example of physical change.
Learn more about physical change here:
https://brainly.com/question/18690541
#SPJ6
Which of the following is a unit for acceleration?
A) m/s
B) m/s2
C) s/m 2
D) s/m
The atomic mass of Gallium is 69.72 AMU. The masses of the naturally occurring isotopes are 68.9257 AMU and 70.908 AMU for Ga-69 and Ga-71. Find the percent (%) abundance for each.
Answer:
40.7% abundance of Ga-71
59.93% abundance of Ga-69
Explanation:
Given data:
Average atomic mass of Ga = 69.72 amu
Atomic mass of Ga-69 = 68.9257 amu
Atomic mass of Ga-71 = 70.908 amu
Percent abundance of each isotope = ?
Solution;
we know there are two naturally occurring isotopes of Ga.
First of all we will set the fraction for both isotopes
X for the isotopes having mass 68.9257
1-x for isotopes having mass 70.908
we will use the following equation,
68.9257x + 70.908 (1-x) = 69.72
68.9257x +70.908 - 70.908x = 69.72
68.9257x - 70.908x = 69.72 - 70.908
-1.9823x = - 1.188
x= 1.188/1.9823
x= 0.5993
0.5993 × 100 = 59.93 %
59.93 % is abundance of Ga-69 because we solve the fraction x.
now we will calculate the abundance of Ga-71.
(1-x)
1 - 0.5993 = 0.4007
0.4007× 100= 40.7 %
40.7 % for Ga-71.
True or False. The speed of light is sped up by dense media.
Answer:
false
Explanation:
According to the laws of reflection, the speed of light is slowed down by denser media, hence the statement is false.
What is reflection?Reflection of light is defined as a property of light ray that when it strikes a smooth surface it bounces back .Objects can be seen due to this property of light.Reflection is produced by all types of waves namely sound waves, light waves, electromagnetic waves.
Reflection of light is governed by laws of reflection which are also called as Snell's laws. According to laws of reflection, angle of incidence and angle of reflection are equal.The incident ray , reflected ray and normal all lie on the same side of the plane.Light travels in a straight line before, after and during the process of reflection.There are 3 types of reflection which are diffuse reflection,specular reflection and glossy reflection.
Learn more about reflection,here:
https://brainly.com/question/2254222
#SPJ2
What is the relationship between the kinetic energy of molecules in a solid and a liquid? Justify your response in two or
more complete sentences.
LEDE
Answer:
In solid the molecules are soo close so tht cant move and also have bonds but in liquid molecules are far and move so thats y liquid don has its own shape
Answer:
In solid the molecules are soo close so tht cant move and also have bonds but in liquid molecules are far and move so thats y liquid don has its own shape
Explanation:
15 Points For A Unnecessary Question, Is It Bad If I Drink Water With Food Coloring?
Yes
No
Answer:no
Explanation:as long as it’s not too much of it then no , it’s not bad . food coloring gets tested to be safe for human consumption so you’re good
Food coloring should be edible and safe on food (hence the name). If it's safe on food, then it should be safe to drink with water. Of course check with the label to be sure.
A Solution is a mixture of two or more substances_____
O a in water
O b. seperate from one another
O c in the same phase
Od come to room temperature
Answer:
In the same phase
Explanation:
Because when you make a solution you have to keep them in the same phase or you will oof.
.
The skydiver will soon open her parachute. How will her velocity change when
the parachute first opens?
Answer:
How will her velocity change when does parachute first open?
The skydiver's weight is balanced by the air resistance. There is no resultant force and the skydiver reaches terminal velocity. When the parachute opens, the air resistance increases. The skydiver slows down until a new, lower terminal velocity is reached.
When a skydiver opens their parachute, they accelerate upwards. This is not the same as saying the move upwards. Acceleration is a change in velocity. They keep feeling an upward force (while moving downward) that slows them until they get to a new terminal velocity.
What force changes when a parachute opens?
An open parachute increases the cross-sectional area of the falling skydiver and thus increases the amount of air resistance which he encounters (as observed in the animation below). Once the parachute is opened, the air resistance overwhelms the downward force of gravity.
What happens if you open the parachute too early?
You are likely to drift off the drop zone. The winds can be pretty heavy at high altitudes, and unless you steer continuously they may blow you off-course. Needless to say, the refrigeration effect of the wind and slipstream will make you feel even colder than the mere altitude. Your landing is likely to be rough.
Explain in steps how to find volume of a rock that is not rectangular water displacement
what is the systematic or IUPAC name for SO2
Answer:
Sulfur trioxide
Sulfur trioxide | SO3 - PubChem.
Explanation:
Protons with different number of nuetrons are called?
Answer:
Atoms of a particular element must have the same number of protons but can have different numbers of neutrons. When an element has different variants that, while all having the same number of protons, have differing numbers of neutrons, these variants are called isotopes.
hope this helps
what are 3 examples of pairs of atoms with polar covalent bonds?
Answer:
Water - H2O
Ammonia - NH3
Sulfur dioxide - SO2
Hydrogen sulfide - H2S
Ethanol - C2H6O
Explanation:
Those are some atoms with polar covalent bonds. Hope this helps!!
what is the primary difference between and hypothesis and a theory
A hypothesis, on the other hand, is similar to a theorem, but it stands pretty much on its own and is not known to be linked to other theorems in any way. A hypothesis usually has no compelling reasons to be true or false. Hypotheses can be classified into the following categories:
The degrees of freedom of a theory have not yet been determined. These could be properties of a theory that haven't been fully determined yet. A theory can be expressed in a finite number of ways, and accepting one of them is referred to as "forming a hypothesis." It's about the aspects of a hypothesis that aren't fully formed yet.Once evidence is discovered, a hypothesis may evolve into a theory.A hypothesis that could become a theory if a mathematical formulation can be established.A hypothesis based on common sense and known theories that is not intended to become part of a bigger theory, but rather to explain a single fact. This could include things like beliefs regarding the formation of the earth.A theory derives a large number of predictions from a limited number of theorems or assumptions, which fall into the following categories:
Things we already knew to be true and can be explained by other theories.Things we previously knew to be true, but which no other theory could explain or predict.Things that we didn't know were true but were later confirmed to be true.Things we didn't realize were true, and don't know if they are still true, but don't contradict current measurements.how many pounds are in 14.8 grams
Answer:
0.03262841
I tried, hope this helps :)
Answer:
0.032 lbs
Explanation:
Divide the mass value by 454.
Nuclear chemistry findings contradict __________________ theory of indivisible atoms.
Answer:
atomic theory
Explanation:
What is the relationship between temperature and pressure?
Write your own response in your own words.
Answer:
Pressure is the force per unit area pounded onto the surface of a container of a gas or liquid. It's interesting to notice that the units of pressure (force/area) are the same as the units of energy density (energy/volume). This gives rise to the interesting result that the pressure at the centers of stars that we think should be sustaining the star against collapse actually attracts more pressure, at high enough pressures, and contributes to collapse
Explanation: this is what i would put ^-^
Select the substance or substances that are homogeneous mixtures
Solution
Compound
Colloid
Molecule
Suspension
Answer:
1 3 6 ones
Explanation:
Answer
Solution Compound Colloid
Explanation:
Calculate the density of a material that has a mass of 52.457 g and a volume of 13.5 cm3.
Answer:
3.8857037037g per cm3
Explanation:
52.357g/13.5 cm3 = 3.8857037037
Round if needed
(C.6a) An atom of a neutral element contains 16 electrons. What element is it?
Answer:
Sulfur
Explanation:
TRUE or FALSE: Any measurement that has been cubed is volume.
Answer:
True
Explanation:
Volume is measured in "cubic" units. The volume of a figure is the number of cubes required to fill it completely, like blocks in a box. Volume of a cube = side times side times side. Since each side of a square is the same, it can simply be the length of one side cubed.
HURRY!! Solve. C3H8(g) + 5O2(g) --> 3CO2(g) + 4H2O(g)
What is the Enthalpy of reaction?
What is the total Enthalpy of Reactants and Products? (Kj/Mol)
Is this a endothermic or exothermic reaction?
Answer: hope this helps!
Explanation:
the number of atoms in 2.0 moles of B is
Answer:
The answer is
1.204 × 10²⁴ atoms of BExplanation:
To find the number of entities of a substance given it's number of moles we use the formula
N = n × Lwhere n is the number of moles
N is the number of entities
L is the Avogadro's constant which is
6.02 × 10²³ entities
From the question
n = 2.0 moles
We have
N = 2 × 6.02 × 10²³
We have the final answer as
1.204 × 10²⁴ atoms of BHope this helps you
Number of moles of boron (B) = 2
To Find :We have to find number of atoms present in the given amount of boron[tex].[/tex]
Solution :➤ We know that 1 mole of substance contains 6.022×10²³ particles (atoms/molecules).
Avogadro's no. = 6.022 × 10²³★ Number of atoms present in B :
⭆ N = n × [tex]\sf{N_A}[/tex]
N denotes number of atomsn denotes mole number[tex]\sf{N_A}[/tex] denotes avogadro's number⭆ N = 2 × 6.022 × 10²³
⭆ N = 12.044 × 10²³
⭆ N = 1.2 × 10²⁴
Hope It Helps!30 Points!! 15 Each Points Please Help ASAP!! View Attached Image!! Will Mark Brainliest If All Are Answered!!
Answer: 22: C
23: A
24: A
25: D
26: B
Explanation: I hope that this helped :)
Answer:
22) b. stainless steel.
23) c. they are all substances.
24) b. a compound can only be separated into its components by chemical means.
25) a. substances are compounds, mixtures are not.
26) b. capitalized
extra: not 100 percent sure of 25
Which statement correctly describes the reactivity of noble gases, according to the octet rule?
Their atoms have one electron in their valence shells, so noble gases are very reactive.
Their atoms have eight electrons in their valence shells, so noble gases are very unreactive.
Their atoms have one electron in their valence shells, so noble gases are very unreactive.
Their atoms have eight electrons in their valence shells, so noble gases are very reactive.
Which event represents a chemical change? A. breaking glass B. chopping wood C. crushing a can D. milk turning sour
Answer:
D
Explanation:
hi! a chemical change changes the composition of the material. in A, even though the glass is broken, it is still glass. for B, even though the wood is chopped, it is still wood. for C, even though the can is crushed, it is still a can. D is a chemical change because the milk's taste changes, meaning its chemical composition changed and a reaction occurred. it is no longer the original milk.
The event represents a chemical change is milk turning sour. Hence option D is correct.
What is chemical change?Chemical change is defined as a transformation of one material into another, the formation of new materials with distinct properties, and the creation of one or more new substances. Chemical synthesis, or, alternatively, chemical breakdown into two or more separate molecules, occurs when one material reacts with another to create a new substance.
In the case of milk, it contains a sugar called lactose as well as lactobacillus, a type of bacteria that is completely safe and uses the lactose to produce energy and lactic acid. This is what gives milk its sour flavor. When the taste of the milk changes, a chemical reaction has taken place, changing its chemical makeup. It isn't the original milk anymore.
Thus, the event represents a chemical change is milk turning sour. Hence option D is correct.
To learn more about chemical change, refer to the link below:
https://brainly.com/question/23693316
#SPJ2
In the outer layer of the sun, energy is transported outward by the rising of hot plasma and sinking of cooler plasma. This transfer is known as __________.
a.Electromagnetic radiation
B.Convection
C. Solar flares
D. Conduction
Answer:
solar flares
Explanation:
We have that The outward transportation of sun rays by the rising of hot plasma and sinking of cooler plasma is Known as
Solar flaresOption D
From the question we are told
In the outer layer of the sun, energy is transported outward by the rising of hot plasma and sinking of cooler plasma. This transfer is known as __
Generally
When the sun give off Heat energy it does this by the rising of hot plasma and sinking of cooler plasma
This Process is defined by scientist around the world as Solar flares and this
is the reason why the rays if the sun reaches earth.
Therefore
The outward transportation of sun rays by the rising of hot plasma and sinking of cooler plasma is Known as
Solar flares
Option D
For more information on this visit
https://brainly.com/question/17756498
The mass of an oxygen–18 atom is 18.0042 amu. Compute the calculated mass.
Answer:
The calculated mass of one atom of oxygen-18 is approximately 2.99×10⁻²³ grams
Explanation:
The given mass of an oxygen-18 atom = 18.0042 amu
The definition of the atomic mass unit is the mass equivalent to the mass of one twelfth the atomic mass of one atom of carbon-12. The atomic mass unit is used to express the mass of an isotope of an element
1 amu = 1.66 × 10⁻²⁴ grams
Therefore;
18.0042 amu = 18.0042 × 1.66 × 10⁻²⁴ grams ≈ 2.99×10⁻²³ grams
The calculated mass of one atom of oxygen-18 ≈ 2.99×10⁻²³ grams
The atomic mass unit can be taken as the mass in grams of one mole of the substance
Therefore, the mass of one mole of the oxygen 18 atom = 18.0042 g
what two elements make up the most of the earth's core
Answer:
The Earth's core is mainly made of iron and nickel.
Explanation:
Answer: The Earth's core is mainly made of iron and nickel.
Explanation:
name the elements that determine the weather of a place....
