TEST QUESTION PLS HELP What are isotopes? Write isotopes of three different elements, showing their atomic number and mass number. (I'll give brainliest)

Answer:

Option B

Explanation:

As Brønsted-Lowry theory states, acids are the ones that can donate protons.

When a proton is donated, it is released to become medium more acidic.

HCl is a strong acid.

HCl (l) + H₂O (l)  →  H₃O⁺ (aq) +  Cl⁻(aq)

These always reffers to strong acid where the dissociation is 100% completed.

In a weak acid, dissociation is not 100% complete, that's why we have an equilibrium.

HA (l) + H₂O (l)  ⇄  H₃O⁺ (aq) +  A⁻(aq)                   Ka

Answer:

According to the kinetic molecular theory, which statement describes the particles in a sample of an ideal gas? The motion of the gas particles is random and in a straight-line.

Explanation:

look at the answerAccording to the kinetic molecular theory, which statement describes the particles in a sample of an ideal gas? The motion of the gas particles is random and in a straight-line.

Answer:

Hydrogen peroxide is not stored in clear bottles because they are transparent and light can easily penetrate through these glass bottles to oxidize into water and oxygen gas

Explanation:

there you go

The volume of H₃PO₄ : 13.33 ml

Given

0.003 M  Phosphoric acid-H₃PO₄

40 ml of 0.00150 M Calcium hydroxide-Ca(OH)₂

Required

Volume of H₃PO₄

Solution

Acid-base titration formula  

Ma. Va. na = Mb. Vb. nb  

Ma, Mb = acid base concentration  

Va, Vb = acid base volume  

na, nb = acid base valence  (amount of H⁺/OH⁻)

H₃PO₄⇒3H⁺ + PO₄³⁻ ⇒ 3 H⁺ = valence = 3

Ca(OH)₂⇒Ca²⁺ + 2OH⁻⇒ 2 OH⁻ = valence = 2

Input the value :

a = H₃PO₄, b = Ca(OH)₂

0.003 x Va x 3 = 0.0015 x 40 x 2

Va = 13.33 ml

Answer:

2.5 grams

Explanation:

law of conservation of mass applies. the magnesium completely burns

Answer:

C would be the right answer

Answer:

B

Explanation:

I have a similar question and it was correct try B

Answer:

Balanced, Unbalanced, Unbalanced, Balanced, Unbalanced.

Explanation:

A student sitting at a desk has no kinetic energy, he/she/they are not moving or exerting force. A rocket taking off is in the process of releasing energy, pushing the rocket upward, attempting to balance the forces of gravity and downward force. A building collapsing has kinetic energy, as gravity has now become greater than that of the force pushing against it. A satellite has balanced force because nothing is acting upon it other than gravity, at which distance, by the fact that is orbiting, is not moving towards or away from the item which has put force on it. When you are in a car at a constant speed, you may move in it as if it is stationary, because the friction on the wheels and wind speed create balanced forces against the engine. From outside of the car, these forces are unbalanced, as the car is propelled, which is what I believe the question is asking.

Hope this helps!

Answer:

C is the correct answer

Explanation:

Answer:

C) 2920 J

Explanation:

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Answer:

it willl have less dense and decreases the voloume of liquid .

Answer:

Stays the same maybe?

Explanation:

Changes in presure have very little effect on the volume of a liquid. Liquids are relatively incompressible because any increase in pressure can only slightly reduce the distance between the closely packed molecules. If the pressure above a liquid is increased sufficiently, the liquid forms a solid.

Answer: 1.31

Explanation:  

No.of moles = given no.of atoms/Avagadro number

= 7.91×10^23 / 6.022 x 10^23

= 1.31

therefore, no.of moles = 1.31

Hope it helped u,

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^_^

Answer:

(1) 3

(2) 12

(3) -ab+4c+5d-5a

Answer:

D. poor conductors of heat ( insulators)

Answer:

Cone Cell

Explanation:

There are about six to seven million cones in a human eye and are most concentrated towards the macula. Cones are less sensitive to light than the rod cells in the retina (which support vision at low light levels), but allow the perception of color.

Answer:

C

Explanation:

C is the only answer that is affected by the color of the wings.

The second volume :    V₂= 0.922 L

7.03 Liters at 31 C and 111 Torr

Required

The second volume

Solution

T₁ = 31 + 273 = 304 K

P₁ = 111 torr = 0,146 atm

V₁ = 7.03 L

At STP :  

P₂ = 1 atm

T₂ = 273 K

Use combine gas law :

P₁V₁/T₁ = P₂V₂/T₂

Input the value :

0.146 x 7.03 / 304 = 1 x V₂/273

V₂= 0.922 L

Answer: it’s not in the first group in the periodic table

Explanation:

Answer:D. 8 grams

Explanation:Took test.

Answer:

Plutonium is the second transuranium element of the actinide series.

The main fuel for a fast neutron reactor is plutonium, which is gradually created in any reactor from non-fissile U-238, which makes up more than 99% of natural uranium. The actinide series' second transuranium element is plutonium.

Pu is the atomic symbol for plutonium, which bears the numbers 94 and 244 in its atomic weight. On a periodic chart, plutonium is located in period 7, which is part of the actinides group.

With an atomic number of 94, plutonium is the second transuranic element and a member of the actinide group on the periodic table. Like its precursor, neptunium, which was named after the planet Neptune, Plutonium is named after the planet Pluto.

To know more about Plutonium, visit;

https://brainly.com/question/13060717

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Mass of SnF2 : 117.53 g

Given

Reaction

Sn(s) + 2HF(g) --> SnF2(s) +H2(g).

30 g of HF

Required

mass of SnF2

Solution

mol HF (MW= 20 g/mol) :

= mass : MW

= 30 : 20

= 1.5

From the equation, mol ratio of HF : SnF2 = 2 : 1, so mol SnF2 :

=1/2 x mol HF

= 1/2 x 1.5

= 0.75

mass SnF2(MW=156.71 g/mol) :

=mol x MW

= 0.75 x 156.71

= 117.53 g

Answer:

0.17 mol

Explanation:

Given data:

Number of atoms of Ar gas = 1.02×10²³ atom

Number of moles = ?

Solution:

The given problem will solve by using Avogadro number.

The number 6.022 × 10²³ is called Avogadro number.

1 mole = 6.022 × 10²³ atoms

1.02×10²³ atom × 1 mol / 6.022 × 10²³ atoms

0.17 mol

Avogadro number:

It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.

Answer:

Nutation

Explanation:

The counterclockwise rotation of planet earth around its own axis is defined as the Earth Rotation. The earth rotates about the line called "the axis of rotation," it is an imaginary line that passes through the North and South Poles of the planet, which the earth rotates about.

Hence, earth rotates once in about 24 hours with respect to the Sun, from West to East and thus giving rise to;

a. Day and night

b. Seasons

The Earth motion which describes the wobbling of the Earth around its precessional axis and could alter the amount of seasonal effects is known as nutation.

Basically, nutation usually occurs when the precessional motion of a planetary body such as planet earth experience some form of irregularities when it is rotating.

The affect of plate movement might have on the size of the ocean basin would be negative and over many millenia it will gradually decrease in size

Answer:3600 meters

Explanation:

If a car travels 60 meters a second for 60 seconds that means it traveled 60*60 meters which is 3600