<em>i think the answer is b </em>
The CaCO3 produced if 47.5 moles of NH3 produced is calculated as follows
CaCN2 +3H2O = CaCO3 + 2NH3
by use of mole ratio between CaCO3 to NH3 which is 1:2 the moles of CaCO3 is therefore = 47.5 /2= 23.75 moles
mass of CaCO3 is therefore = moles x molar mass
= 23.75 moles x 100g/mol= 2375 grams which is approximate 2380 grams(answer 6)
Phenolphthalein
In acid it is colourless and in water also colourless
Answer:1 mol of Mg(NO3)2 contains 6.022*10^23 molecules
3 mol Mg(NO3)2 contains 3*6.022*10^23 = 1.81*10^24 molecules
Each Mg(NO3)2 molecule contains 2 N atoms
Number of N atoms = 2*1.81*10^24 = 3.62*10^24 N atoms.
Of course, at STP, dioxygen is a gas, but 10.0 g is still 10.0 g. We could calculate its volume at STP, which is 22.4 L × its molar quantity, approx. 8⋅L . There are 1.51×1023molecules O2 in 10.0 g O2 .
