Answer:- Mass of the alloy is 2.8 kg.
Solution:- Mass of Cr in the alloy is 325 g and mass of Fe in the alloy is 2.5 kg. Mass of alloy would be the sum of masses of constituent metals.
Masses of the metals are not in the same units. So, we need to make the units equal. The want answer in kg so let's convert mass of Cr from g to kg.
Since, 1000 g = 1 kg
So, 
= 0.325 kg
Mass of alloy = mass of Cr + mass of Fe
mass of alloy = 0.325 kg + 2.5 kg = 2.825 kg
If we consider significant figures then as per the rules, the answer should not have more than one decimal place.
So, 2.825 kg is round off to 2.8 kg and hence the mass of the alloy is 2.8 kg.
Balance the equation first:
2 Fe+6 HNO3→2 Fe(NO3)3+3H2
Then calculate mass of Iron :
4.5×3.0×3.5 cm3(1 mL1 cm3)(7.87 g Fe1 ml)=371.86 g Fe
Now use Stoichiometry:
371.86 g Fe×(1 mol Fe55.85 g Fe)×(6 mol HNO32 mol Fe)=19.97 mol HNO3
Convert moles of nitric acid to grams
19.97 mol HNO3×(63.01 g HNO31 mol HNO3)=1258.3 g HNO3
Answer: 1. 1.59 x 10^23 Particles
2. 4.79 x 10^21 particles
3. 2.67 x 10^25 particles
4. 2.12 x 10^23 Particles
Explanation: 1mole of any substance contains 6.02x10^23 Particles
1. 0.264 mol of silver will contain = 0.264 x 6.02x10^23 = 1.59 x 10^23 Particles
2. 7.95 x 10^-3 mol sodium chloride will contain = 7.95 x 10^-3 X 6.02x10^23 = 4.79 x 10^21 particles
3. 44.4 mol carbon dioxide will contain = 44.4 x 6.02x10^23 = 2.67 x 10^25 particles
4. 0.352 mol nitrogen will contain = 0.352 x 6.02x10^23 = 2.12 x 10^23 Particles
Answer:
the third one because oceans don't affect the weather
Explanation:
