Purple stem plants can be formed by genetics, they use their energy slightly different from other plants, they use less energy, but that may also be because of bad nutrition, and because they may be hungry for nutrients.
Answer:
A) Sample B has more calcium carbonate molecules
Explanation:
M = Molar mass of calcium carbonate = 100.0869 g/mol
= Avogadro's number = 
For the 4.12 g sample
Moles of a substance is given by

Number of molecules is given by

For the 19.37 g sample

Number of molecules is given by


So, sample B has more calcium carbonate molecules.
The ratio of the elements of carbon, oxygen, calcium atoms, ions, has to be same in both the samples otherwise the samples cannot be considered as calcium carbonate. Same is applicable for impurities. If there are impurites then the sample cannot be considered as calcium carbonate.
<em>Answer:</em>
<em>Chemical equations must be balanced to satisfy the law of conservation of matter, that states that matter cannot be produced or destroyed in a closed system. The law of conservation of mass governs the balancing of a chemical equation.</em>
Explanation:
Answer:
The first 5 are exothermic reaction because heat is in product means heat is evolved or given out.
And last no reaction shows that heat is required so last reaction is endothermic reaction.
Explanation:
And heat is evolved in exothermic reaction and heat is absorbed in endo thermic reaction