<span>Balanced nuclear reaction: 234/91 Pa → 4/2 He + 230/89 Ac.
1) number of protons and neutrons on both side of nuclear reaction must be the same. There are 91 protons (atomic number) and 143 neutrons (mass number - atomic number, 234 - 91 = 143 or (4-2) + (230 - 89) = 143)) on both side of reaction.
2) a</span>lpha
decay is radioactive decay<span> in which
an atomic nucleus emits
an alpha particle (helium
nucleus) and transforms into an atom with an atomic
number that is reduced by two and mass number that is reduced by four, so atomic mass of new element is 89 (91 - 2) and mass number is 230 (234 - 4 = 230).
3) look at atomic number, element with atomic number 89 is actinium.</span>
Answer:
Magnesium
Explanation:
When an atom loses are gain the electrons ions are formed.
There are two types of ions.
Anion
Cation
1 = Anion
It is formed when an atom gain the electrons. when atom gain electron negative charge is created on atom. For example.
X + e⁻ → X⁻
2= Cation
It is formed when an atom loses the electrons. when atom lose electron positive charge is created on atom. For example.
X → X⁺ + e⁻
There are seven valance electrons in iodine. To complete the octet it gain one electron and form anion.
Sulfur has six valance electrons it gain two electrons to complete the octet and form anion.
Phosphorus has five valance electrons it gain three electrons two complete the octet and form anion.
Magnesium has two valance electrons it loses two electron to complete the octet and form cation.
Answer:
162.7miles/hr
Explanation:
Given parameters:
Distance covered by the train = 813.5miles
Time taken = 5hours
Unknown:
Speed of the train = ?
Solution:
Speed is a physical quantity.
It is mathematically expressed as;
Speed = 
So, input parameters and solve;
Speed = 
= 162.7miles/hr
These oppositely charged compounds are strongly held by electrostatic forces of attraction as these be together for a long time the rise in temparature occurs so that the the melting points rises in them.
Answer:
SO₃(g) + H₂O(l) → H₂SO₄(aq)
Explanation:
The<em> molecular formula for the involved species</em> are:
- Sulfur trioxide = SO₃. ("trioxide" indicates the presence of 3 oxygen atoms).
With the above information in mind we can proceed to write the reaction equation:
- SO₃(g) + H₂O(l) → H₂SO₄(aq)
