1,38×10²² = 0,138×10²³
0,138×10²³ ----- 1,5g
6,02×10²³ ------ X
X = (1.5×6,02×10²³)/0,138×10²³
X = 65,435 g/mol
It's ZINC (Zn)
:•)
Answer:

Explanation:
The Rydberg equation gives the wavelength λ for the transitions:

where
R= the Rydberg constant (1.0974 ×10⁷ m⁻¹) and

Data:

λ = 657 nm
Calculation:

We are asked to solve for the arc length of the intercepted arc and the formula is shown below:
Arc length = 2*pi*r(central angle/360°)
r = 5 feet
central angle = 10°
Solving for the arc length, we have:
Arc length = 2*3.14*5 (10/360)
Arc length = 0.872 feet
The arc length is 0.872 feet.
Answer:
Volume of the cube is 2*2*2 = 8cm^3.
Divide the weight (40g) over the volume (8cm^3).
Density is 5g/cm^3. Definitely not gold.
Explanation:
Answer: Since the reaction is 2Ca(NO3)2 = 2CaO + 4NO2 + O2
1) - given the stoichiometric coefficients, we know that 2 moles of Ca(NO3)2 will produce 4 moles of NO2, hence, 1 mole will produce 2 moles of NO2
2) - 328 g produces 22.4 L, since One mole of any gas at S.T.P. occupies the same volume which is 22.4 L.
Hence, 65.6 g produces (65.6*22.4)/328 = 4.48 L
3) - 328 g produces 112 g CaO. Therefore, 65.6 g produces = (65.6*112)/328 = 22.4 g CaO.
4) - Given the stoichiometric coefficients, we know 5 moles of gaseous products are already being produces ( 4+1) by 2 moles of reactant.
5) - 44.8 L at STP = 2 moles of NO2, since One mole of any gas at S.T.P. occupies the same volume which is 22.4 L.
Hence, to produce 2 moles of NO2, we need 1 mole of reactant = 164 g
Hope this helps :)
Explanation: