Answer:
1. 9.57 × 10^-9 moles.
2. 7.38mol
Explanation:
1.) To find the number of moles there are in the number of particles in an atom, we divide the number of particles (nA) by Avagadro's constant (6.02 × 10^23)
Hence, to find the number of moles (n) of Manganese (Mn), we say:
5.76 x 10^15 atoms ÷ 6.02 × 10^23
5.76/6.02 × 10^(15-23)
= 0.957 × 10^-8
= 9.57 × 10^-9 moles.
2.) Mole = mass/molar mass
Molar mass of sodium chloride (NaCl) = 23 + 35.5
= 58.5g/mol
mole = 431.6 g ÷ 58.5g/mol
mole = 7.38mol
Answer:
a) r = k × [A] × [B]²
b) 3
Explanation:
Let's consider the following generic reaction
A + B + C ⇒ Products
The generic rate law is:
r = k × [A]ᵃ × [B]ᵇ × [C]ⁿ
where
This reaction is first order in A, second order in B, and zero order in C. The rate law is:
r = k × [A]¹ × [B]² × [C]⁰
r = k × [A] × [B]²
The overall order of the reaction is the sum of the individual reaction orders.
1 + 2 + 0 = 3
What amount of heat absorbs 50 g of steel (ce = 0.115 cal / g. ° C) that
does its temperature vary by 25 ° C?
Answer:
143.75cal
Explanation:
Given parameters:
Mass of steel = 50g
Specific heat capacity of the steel = 0.115cal/g°C
Temperature = 25°C
Unknown:
Amount of heat = ?
Solution:
The amount of heat to cause this temperature change is dependent on mass and specific heat capacity of the substance.
Amount of heat = m C (ΔT)
m is the mass
c is the specific heat capacity
ΔT is the temperature change
Now insert the parameters and solve;
Amount of heat = 50 x 0.115 x 25
Amount of heat = 143.75cal
Melamine should be the right answer, i hope this helps.
Answer:
Explanation:
Hello!
In this case, as we know the mass of the total sample, we can first compute the mass of oxygen:
Next, we compute the moles of each element:
Now, we divide the moles by 0.184 moles, the fewest ones, to obtain:
Therefore, the empirical formula is:
Regards!
