1.38 moles of oxygen
Explanation:
Thermal decomposition of Lead (II) nitrate is shown by the balanced equation below;
2Pb(NO₃)₂ → 2PbO + 4NO₂ + O₂
The mole ration of Lead (II) nitrate to oxygen is 2: 1
Therefore 2.76 moles of Lead (II) nitrate will lead to production of? moles of oxygen;
2: 1
2.76: x
Cross-multiply;
2x = 2.76 * 1
x = 2.76 / 2
x = 1.38
Answer:
Because you can physically see the object melting when it comes to the melting point. The objects texture, color, temperature, shape, and state of matter (solid, liquid, gas) are possibly changing.
Answer:

Explanation:
Given:
For a school event, 1/6 of the athletic field is reserved for the fifth -grade classes and the reserved part of the field is divided equally among the 4 fifth grade classes in the school.
To find: fraction of the whole athletic field reserved for each fifth class
Solution:
Fraction of the whole athletic field reserved for four fifth classes = 
So, fraction of the whole athletic field reserved for each fifth class = 
.sand and water
.iron fillings in a liquid
.cereal in milk
Half life is the time taken for a radioactive isotope to decay by half its original mass. In this case the half life of carbon-14 is 5.730 years.
Using the formula;
New mass = original mass × (1/2)^n; where n is the number of half lives (in this case n=1 )
New mass = 2 g × (1/2)^1
= 1 g
Therefore; the mass of carbon-14 that remains will be 1 g