The answer is (2). To calculate the density, you need to divide the mass with volume. When doing division, the significant figures of result is the minimal of the numbers using before. So the answer is 2.
<span>a.) the energy involved in the phase changes</span>
30 % of vegetables and 20% of fruits
So B) 50%
<u>Answer:</u> The mass of the new compound formed will be 159 grams.
<u>Explanation:</u>
Synthesis reaction is defined as the reaction in which smaller substances combine in their elemental state to form a larger substance.
Law of conservation of mass states that mass can neither be created nor be destroyed but it can only be transformed from one form to another form.
This also means that total mass on the reactant side must be equal to the total mass on the product side.
The chemical equation for the synthesis of copper oxide follows:
Let the mass of new compound (copper oxide) formed be 'x' grams
We are given:
Mass of copper metal = 127 grams
Mass of oxygen gas = 32 grams
Total mass on reactant side = 127 + 32 = 159 g
Total mass on product side = x
So, by applying law of conservation of mass, we get:
x = 159 g
Hence, the mass of the new compound formed will be 159 grams.