B. reproduction doesn’t require mate
Answer:
It becomes negative
Explanation:
protons carry a positive charge
neutrons carry a neutral charge
electrons carry a negative charge
if we add 2 more electrons, the charge of the ion becomes negative
thank you.
The ore contains 55.4% calcium phosphate (related to the mineral apatite) so the amount of Ca3(PO4)2 is 55.4%x=1000g so x=1000/0.554= 1.805kg. Now for the % of P in this amount of calcium phosphate, use all the masses of the elements in Ca3PO4= Ca=40.078 x 3= 120.23 and (PO4)2= (30.974+64)2=189.95 (NB oxygen is 16 mass x 4 =64) so the total mass is 310.2 and we have 61.95 of P (Pmass x 2) so 61.95/3102.= 0.19 or 19% P. So of the 1.805 x 0.19= 0.34kg of phosphorus.
Answer: 35.1 kJ/mol
Explanation:
According to Hess’s law of constant heat summation, the heat absorbed or evolved in a given chemical equation is the same whether the process occurs in one step or several steps.
According to this law, the chemical equation can be treated as ordinary algebraic expression and can be added or subtracted to yield the required equation. That means the enthalpy change of the overall reaction is the sum of the enthalpy changes of the intermediate reactions.
(1)
(1)
The final reaction is:
(3)
By adding (1) and (2)
Hence the expected value for the heat of sublimation of acetic acid is 35.1 kJ/mol
<h2>
Answer: 8.69 × 10⁻¹ Hz
</h2>
<h3>
Explanation:
</h3>
Frequency = Speed of Light ÷ Wavelength
= (2.99 × 10⁸ m/s) ÷ (3.44 × 10⁻⁸ m)
= 8.69 × 10⁻¹ Hz
The frequency of a light of wavelength 34.4 nm is 8.69 × 10⁻¹ Hz.
<u>Notes:</u>
Hz ≡ /s
1 m = 10⁹ nm
