Answer:
A
Explanation:
Hot air is less dense therefore it rises. Cold air is more closely packed therefore it is more dense. Less dense things rise while more dense things sink.
The balanced equation for the above reaction is as follows;
<span>Fe</span>₂<span>O</span>₃<span> + 3 CO --> 2 Fe + 3 CO</span>₂
<span>stoichiometry of CO to Fe is 3:2
molar volume states that 1 mol of any gas occupies a volume of 22.4 L
If 22.4 L contains 1 mol of CO
Then 3.65 L contains - 1/22.4 x 3.65 = 0.16 mol
3 mol of CO forms 2 mol of Fe
Then 0.16 mol of CO forms - 2/3 x 0.16 = 0.1067 mol of Fe
Therefore mass of Fe produced - 0.1067 mol x 55.8 g/mol = 5.95 g</span>
Answer:
By repelling water, the tiny water striders stand on the water's surface and the captured airs allows them to float and move easily. so number 2. Surface Tension.
Explanation:
The attraction between water molecules creates tension and a very delicate membrane. Water striders walk on this membrane. ... The legs have tiny hairs that repel water and capture air.
339 grams of CLF3 is formed when F2 is in excess and 130 grams of CL2 reacts.
Explanation:
The balanced chemical reaction for the formation of ClF3 is given by:
+ 3 
⇒ 2 Cl
the mass of Cl2 is given 130 grams
From the equation it is found that 2 moles of chloride reacts to form 2 moles of ClF3.
calculating the number of moles of chlorine by the formula:
Number of moles = mass of the substance ÷ atomic mass of one mole of the substance
n = 130 ÷ 35.45
= 3.6671 moles
So, applying stoichiometry
2 moles of Cl2 formed 2 moles of ClF3
3.6671 moles of Cl2 will form x moles of ClF3
2 ÷ 2 = x ÷ 3.6671
x = 3.6671 moles of ClF3
now from the formula of number of moles
weight is calculated as n × mass of the gas
3.6671 × 92.448
= 339.01 grams of ClF3 is formed.
Answer:
2.49×10²⁰ atoms of Pb
Explanation:
This a problen that can be solved with a rule of three:
1 atom of Pb weighs 3.44×10⁻²² g
Let's convert the mass from mg to g → 85.9 mg . 1g / 1000mg = 0.0859 g
Now, the rule of three:
3.44×10⁻²² g is the weight for 1 atom
0.0859 g is the weight for ( 0.0859 g . 1) / 3.44×10⁻²² g = 2.49×10²⁰ atoms of Pb
