Covalent for the first one
Answer:
For most of its active life, a star shines due to thermonuclear fusion of hydrogen into helium in its core, releasing energy that traverses the star's interior and then radiates into outer space. At the end of a star's lifetime, its core becomes a stellar remnant : a white dwarf , a neutron star , or, if it is sufficiently massive, a black hole .
Explanation:
A) Magnesium + Chlorine -> Magnesium chloride ( Mg + Cl2 -> MgCl2)
b) Potassium + Oxygen -> Potassium oxide
( 2K + O2 -> K2O )
c) Sodium + Bromine -> Sodium bromide
( 2Na + Br2 -> 2NaBr)
d) Carbon + Oxygen -> Carbon dioxide
( C + O2 -> CO2 ) This reaction occurs when heated.
Decay constant, proportionality between the size of a population of radioactive atoms and the rate at which the population decreases because of radioactive decay.
<h3>What is decay constant value?</h3>
The rate of disintegration is proportional to the number of atoms at any point in time and the constant of proportionality is called the radioactivity decay constant. The radioactive decay constant for Radium B is approximately 4.3 × 10−4 s−1.
<h3>What is decay constant unit?</h3>
Definition. The decay constant (symbol: λ and units: s−1 or a−1) of a radioactive nuclide is its probability of decay per unit time. The number of parent nuclides P therefore decreases with time t as dP/P dt = −λ. The energies involved in the binding of protons and neutrons by the nuclear forces are ca.
Learn more about decay constant here:
<h3>
brainly.com/question/16623902</h3><h3 /><h3>#SPJ4</h3>
25*5= 225 and 7hs hsueuxn udneicj
