Answer:
In the lab, students were encouraged to look at different types of rocks and minerals. They were also told to observe the physical properties of the rocks and minerals. Based on these physical properties, the children were able to distinguish the different types of rocks and minerals. The major differences which the children will focus on will be the color, shape, hardness, luster, streak, fracture and cleavage of the rocks and minerals.
O is what should go in the blank. O stands for Oxygen.
The enthalpy change of the reaction when sodium hydroxide and sulfuric acid react can be calculated using the mass of solution, temperature change, and specific heat of water.
The balanced chemical equation for the reaction can be represented as,

Given volume of the solution = 101.2 mL + 50.6 mL = 151.8 mL
Heat of the reaction, q =
Δ
m is mass of the solution = 151.8 mL * 
C is the specific heat of solution = 4.18 
ΔT is the temperature change = 
q = 
Moles of NaOH =
NaOH
Moles of
= 
Enthalpy of the reaction = 
Answer:
D 2,2
Explanation:
We can see that there are 2 chlorines on the reactant side so there has to be a 2 on the product side
Now we have Na + Cl2 --> 2NaCl
The problem now is that there are 2 sodiums on the product side so add a 2 to the Na on the reactant side
2Na + Cl2 --> 2NaCl
Now it's balanced!
The question ask for the percentage of the abundance of galium-69 where there is two isotopes of galium: the 69Ga and the 71Ga. The average atomic mass of gallium is 69.723 amu. So the formula would be <span>69.723amu=(%x)∗(68.926amu)+(1−%x)∗(70.025amu) and the answer to this is 1.58%</span>