Which nuclear equation represents a spontaneous decay?

(1) Rn 21% Po + He

(2) 13 Al + He 18P + on

(3) 235 U + in ~ 13% Ba + Kr + 3n

(4) Li + H → He + He

a. 1

b. 2

C 3

d. 4

The volume of Carbon dioxide at STP = 209.22 L

Given

411g of Carbon dioxide gas

Required

The volume of Carbon dioxide

Solution

mol of Carbon dioxide :

= mass : MW CO₂

= 411 g : 44 g/mol

= 9.34

Conditions at T 0 ° C and P 1 atm are stated by STP (Standard Temperature and Pressure). At STP, Vm is 22.4 liters/mol.

So for 9.34 mol :

= 9.34 x 22.4 L

= 209.22 L

Answer:

Fe³⁺

Explanation:

When Fe²⁺ loses an electron, it becomes an Fe³⁺ ion.

   The loss of an electron in an atom makes the atom becomes positively charged. Further losing electrons makes the atom more positive.

 For the given ion;

 Fe²⁺   if it loses an electron more, it becomes Fe³⁺.

The expression is given as:

         Fe²⁺    →    Fe³⁺  +  e⁻

Answer: b should be the answer just took this test

Explanation:

Answer:

2 vials

Explanation:

The concentration (C) of the drug in the solution is:

C= 500 mg/5 mL = 100 mg/mL

Each vial with a volume (V) of 10 mL, contains the following mass of drug:

V= 10 mL ⇒ C x V = 100 mg/mL x 10 mL = 1000 mg

As you need 2.00 g, and 1 gram is equivalent to 1000 mg, the mass needed is 2.00 g x 1000 mg/1 g = 2000 mg

Thus, you have to divide the mass you need into the mass of each vial:

(2000 mg)/(1000 mg/vial) = 2 vials

Therefore, you need 2 vials.

Answer:

the answer would be B

Explanation:

The move vigorously it is the higher the reactivity so if you put it in order the answer would be B

Atomic number equals the number of protons or electrons. Atomic mass equals the number of protons and neutrons

Answer:

× = and

Explanation:

person and person

Explanation:

Molar mass of Hg = 200.59g/mol.

Therefore Moles = Mass / Molar mass

= 100g / (200.59g/mol) = 0.499mol.

Answer:

45.7

Explanation:

Because if the number 1-4 then it goes down and if it 5-9 then it goes up

Answer:

In general, the trend in atomic radius as the atomic number in a vertical column of the periodic table increases is to increase.

Explanation:

The atomic radius represents the distance between the nucleus and the valence shell (that is, the outermost). By means of the atomic radius it is possible to determine the size of the atom.

In groups, the atomic radius increases with the atomic number, that is, down a column. This is because as the atomic number of the elements in a group increases, the number of occupied levels increases, while the effective nuclear charge on the outermost electron is the same. Consequently, the atomic radius increases.

In other words, when you go down in a group (column) of the periodic table, the effective nuclear charge increases, but the number of electrons added with respect to the previous element, the same group increases in a complete shell. The effect of adding new electronic shells is predominant, so they are increasingly distant from the atomic nucleus and the atomic radius is greater when you go down in a group.

So the increase in atomic radius as you go down in a group is due to the increase in electron shells.

Answer:

It’s either A or D  buttttt probably d

Explanation:

Answer:

Fnet = 20 Newton

Explanation:

Let the force applied by Brian be Fb.

Let the force applied by Alice be Fa.

Given the following data;

Force, Fb = 10N

Force, Fa = 30N

To find the net force, Fnet;

Net force can be defined as the vector sum of all the forces acting on a body or an object i.e the sum of all forces acting simultaneously on a body or an object.

Mathematically, net force is given by the formula;

[tex] Fnet = Fapp + Fg[/tex]

Where;

Since the two force applied to the box are acting in opposite direction, we would subtract their values to find the net force.

Fnet = Fa - Fb

Fnet = 30 - 10

Fnet = 20 Newton

Answer:

I hope this photo can help you.

Moles of Oxygen= 2.8075 moles

Given

29.2 grams of acetylene

Required

moles of Oxygen

Solution

Reaction(Combustion of Acetylene) :

2 C₂H₂ (g) + 5 O₂ (g) ⇒ 4CO₂ (g) + 2H₂O (g)

Mol of Acetylene :

= mass : MW Acetylene

= 29.2 g : 26 g/mol

= 1.123

From equation, mol ratio of Acetylene(C₂H₂) : O₂ = 2 : 5, so mol O₂ :

= 5/2 x mol C₂H₂

= 5/2 x 1.123

= 2.8075 moles

Answer:ionic

Explanation: ionic bond formation

In the ionic bond formation between calcium and sulfur, a calcium atom donates two valence electrons to a sulfur atom to form a Ca2+ ion and an S2+ ⁻ ion.

Answer:C

Explanation:

Answer:

It's B I promise you

Answer:

1.63 mols

Explanation:

to convert mols to formula unit, or formula unit to mols, u need the avagadros number which is 6.022*10^23 and the number of mols/formula units

so since the given is formula units, u just have to divide the number by 6.022*10^23 to get the amount of mols

9.82*10^23 / (6.022*10^23) = 1.63 mols

*be careful for sig figs

Answer:

In chemistry and physics, quantum refers to a single packet of matter or energy. In practical use, it refers to the minimum amount of energy required for a change or the minimum value of any physical property in an interaction. Quantum is the singular form of the word. Quanta is the plural form of the term.

Explanation:

Answer:

quantum of energy

Explanation:

The term quantum of energy means that the energy is not transferred continuously but as discrete packets of energy. Amount of energy required to move an electron from one energy level to another. The amount of energy an electron gains or loses is. Not always the same. The higher energy levels are.

hope it helps!

Answer:

(1) The two column proof is presented here as follows;

Statement         [tex]{}[/tex]                                Reasons

1. C is the midpoint of [tex]\overline {AE}[/tex]         [tex]{}[/tex]           Given  

  B is the midpoint of [tex]\overline {AC}[/tex]         [tex]{}[/tex]          

  D is the midpoint of [tex]\overline {CE}[/tex]         [tex]{}[/tex]          

2. AC = CE, AB = BC, CD = DE        [tex]{}[/tex]      Definition of midpoint

3. AB + BC = AC, CD + DE = CE      [tex]{}[/tex]       Segment addition postulate

4. CD + DE = AC        [tex]{}[/tex]                             Substitution property of equality

5. AB + BC = CD + DE  [tex]{}[/tex]                          Substitution property of equality

6. BC + BC = CD + CD          [tex]{}[/tex]                  Substitution property of equality

7. 2·BC = 2·CD         [tex]{}[/tex]                               Addition of two identical quantities

8. BC = CD  [tex]{}[/tex]                                            Division property of equality

9. BC ≅  CD     [tex]{}[/tex]                                       Definition of Congruence

(2) The two column proof for the triangular geometric figure is presented here as follows;

Statement         [tex]{}[/tex]                                        Reasons

1. 2·WV = XY; 2·YZ = XW; WV = YZ   [tex]{}[/tex]      Given

2.  2·WV = 2·YZ        [tex]{}[/tex]                                Multiplication property

3. XY = XW        [tex]{}[/tex]                                       Substitution Property

4. XW + WV = XV       [tex]{}[/tex]                              Segment Addition Property

XY + YZ = XZ

5. XW + WV = XV      [tex]{}[/tex]                              Substitution Property

XW + WV = XZ

6. XV = XZ       [tex]{}[/tex]                                        Substitution Property

Explanation:

Given :

A gas with a volume of 2 L at 25°C is placed into a container that is 4 L.

To Find :

The new temperature of the gas.

Solution :

Since, their is no information regarding pressure. We will assume that pressure is constant.

Now, we know when at constant pressure, volume is directly proportional to volume.

[tex]\dfrac{V_1}{V_2}=\dfrac{T_1}{T_2}\\\\\dfrac{2}{4} = \dfrac{25 + 273 }{x}\\\\x = 2 \times ( 25 + 273 )\\\\x = 596\ K[/tex]

Therefore, the new temperature of the gas is 596 - 273 K = 323  K.

Answer:

it helps them fly (A)

Explanation:

Answer:

strengths wings?

Explanation:

If I'm right, please give brainliest?

Answer:

(a) there are strong forces (of attraction) between the particles in a solid

accept molecules / atoms for particles throughout

accept bonds for forces

1

(holding) the particles close together

particles in a solid are less spread out is insufficient

1

or

(holding) the particles in a fixed pattern / positions

but in a gas the forces between the particles are negligible

accept very small / zero for negligible

accept bonds for forces

1

so the particles spread out (to fill their container)

accept particles are not close together

gas particles are not in a fixed position is insufficient

Explanation:

Answer:

complex

Explanation:

becaause it fits in the words equation I hoped i helped

Answer:

See explanation

Explanation:

There are two chemicals commonly used to test for water. They are;

CuSO4: Anhydrous CuSO4  is white in colour, when it absorbs moisture, its colour changes from white to blue.

CoCl2: Anhydrous CoCl2 is blue in colour. when it absorbs moisture, its colour changes from blue to pink.