Answer:
6. 7870 kg/m³ (3 s.f.)
7. 33.4 g (3 s.f.)
8. 12600 kg/m³ (3 s.f.)
Explanation:
6. The SI unit for density is kg/m³. Thus convert the mass to Kg and volume to m³ first.
1 kg= 1000g
1m³= 1 ×10⁶ cm³
Mass of iron bar
= 64.2g
= 64.2 ÷1000 kg
= 0.0642 kg
Volume of iron bar
= 8.16 cm³
= 8.16 ÷ 10⁶
Density of iron bar
= 7870 kg/m³ (3 s.f.)
7.
Mass
= 1.16 ×28.8
= 33.408 g
= 33.4 g (3 s.f.)
8. Volume of brick
= 12 cm³
Mass of brick
= 151 g
= 151 ÷ 1000 kg
= 0.151 kg
Density of brick
= mass ÷ volume
(3 s.f.)
Soil covered, saturated, submerged, flooded w water, standing water
I’m pretty sure it’s D.increases the activation energy for a reaction.
Answer: 460.624
Explanation:
1. Multiply the numbers
(24.5260 x 2.56) + 397.84
= (62.784) + 397.84
2. Add the numbers
(62.784) + 397.84
= 460.624
This problem is very easy to answer. You simply have to look at the subscripts of each element of the compound.
1. For caffeine, which has a molecular formula of C₈H₁₀N₄O₂, it contains 8 atoms of Carbon, 10 atoms of Hydrogen, 4 atoms of Nitrogen and 2 atoms of Oxygen.
2. For Iron(III) Sulfate, which has a molecular formula of Fe₂(SO₄)₃, it contains 2 atoms of Iron, 3 atoms of Sulfur, and 12 atoms of Oxygen.
