Answer:
b) 2.0 mol
Explanation:
Given data:
Number of moles of Ca needed = ?
Number of moles of water present = 4.0 mol
Solution:
Chemical equation:
Ca + 2H₂O → Ca(OH)₂ + H₂
now we will compare the moles of Ca and H₂O .
H₂O : Ca
2 : 1
4.0 : 1/2×4.0 = 2.0 mol
Thus, 2 moles of Ca are needed.
Answer:
Breaks down and absorbs nutrients from the food and liquids you consume to use for important things like energy, growth and repairing cells.
Hthe heat required to change the temperfature of 100 grams of water from 25 to 55 c is calculated as below
Q(heat) = M(mass) x C(specific heat capacity) x delta T(change in temperature)
M= 100 grams
C= 4.18 j/g/c
delta T= 55-25 =30c
Q=100 g x4.814 j/g/c x 30c = 12552 joules
There are 94 naturally occurring elements
