Yes, especially if its from a lake, pond, or ocean since water moves around. Dinasours could have spit out or maybe dripped some water, so basically yes.
By adding the enthalpies of the intermediate reactions together to get the enthalpy of the desired reaction
Here we have to choose the right option which tells the moles of CaCl₂ will react with 6.2 moles of AgNO₃ in the reaction
2AgNO₃ + CaCl₂→ 2AgCl + Ca(NO₃)₂
6.2 moles of silver nitrate (AgNO₃) will react with B. 3.1 moles of calcium chloride (CaCl₂).
From the reaction: 2AgNO₃ + CaCl₂→ 2AgCl + Ca(NO₃)₂
Thus 2 moles of AgNO₃ reacts with 1 mole of CaCl₂
Henceforth, 6.2 moles of AgNO₃ reacts with 
= 3.1 moles of CaCl₂.
1 mole of CaCl₂ reacts with 2 moles of AgNO₃. Thus-
A. 2.2 moles of CaCl₂ will react with 2.2×2 = 4.4 moles of AgNO₃.
C. 6.2 moles of CaCl₂ will reacts with 6.2×2 = 12.4 moles of AgNO₃.
D. 12.4 moles of CaCl₂ will reacts with 12.4 × 2 = 24.8 moles of AgNO₃
Thus the right answer is 6.2 moles of AgNO₃ will react with 3.1 moles of CaCl₂.
Because metals that are more reactive than carbon wont react with it.
<span>1. A cylinder is submerged in water as illustrated in the diagram. Which of the following statements is true?
</span><span>The pressure at D is greater than at B. This is because D is trying to get back to the surface with an amount of pressure. B has less amount of pressure.
</span><span>2. A cylinder is submerged in water as illustrated in the diagram. If the area of the top and the bottom of the cylinder is the same, which of the following statements is true?
</span><span>buoyant force = (force D - force A).
Edit: If you ever notice. When you fill a sink full of water. Put a glass upside down and try forcefully to submerge it under the water it will resist. This is because of the pressure and air. The glass is less dense then water. (Also depends on the glass)</span>
