Answer:
surrounded by two membranes
Explanation:
The nucleus is surrounded by two unit membranes. Together, the two membranes of the nucleus make the nuclear envelope. Therefore, the nucleus is said to be a double membrane-bound organelle. Likewise, chloroplast and mitochondria are also surrounded by two unit membranes and both are the double membrane-bound organelles. Like the nucleus, both chloroplast and mitochondria have their own DNA.
Answer:
0.062 moles of hydrogen gas
Explanation:
We must first out down the reaction equation before we can attempt to solve the problem.
Mg(s) + 2HCl(aq) ----> MgCl2(aq) + H2(g)
Next we obtain the number of moles in 1.5 g of magnesium metal from;
Molar mass of magnesium = 24.3 gmol-1
Number of moles of magnesium= mass/molar mass = 1.5g/24.3gmol-1 = 0.062 moles
From the reaction equation;
1 mole of magnesium metal yields 1 mole of hydrogen gas
0.062 moles of magnesium metal will yield 0.062 moles of hydrogen gas
Therefore, reaction of 1.5g of magnesium metal with excess hydrochloric acid will yield 0.062 moles of hydrogen gas.
It’s discover that plants and animale are mad of cells