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
![= 8.16 \times 10^{ - 6} \: kg](https://tex.z-dn.net/?f=%20%3D%208.16%20%5Ctimes%2010%5E%7B%20-%206%7D%20%5C%3A%20%20kg)
![\boxed{density = \frac{mass}{volume} }](https://tex.z-dn.net/?f=%5Cboxed%7Bdensity%20%3D%20%20%5Cfrac%7Bmass%7D%7Bvolume%7D%20%7D)
Density of iron bar
![= \frac{0.0642}{8.16 \times 10^{ - 6} }](https://tex.z-dn.net/?f=%20%3D%20%20%5Cfrac%7B0.0642%7D%7B8.16%20%5Ctimes%2010%5E%7B%20-%206%7D%20%7D%20)
= 7870 kg/m³ (3 s.f.)
7.
![\boxed{mass = density \: \times volume}](https://tex.z-dn.net/?f=%5Cboxed%7Bmass%20%3D%20density%20%5C%3A%20%20%5Ctimes%20volume%7D)
Mass
= 1.16 ×28.8
= 33.408 g
= 33.4 g (3 s.f.)
8. Volume of brick
= 12 cm³
![= 12 \times 10^{ - 6} \: m^{3} \\ = 1.2 \times 10^{ - 5} \: m ^{3}](https://tex.z-dn.net/?f=%20%3D%2012%20%20%5Ctimes%20%2010%5E%7B%20-%206%7D%20%20%5C%3A%20m%5E%7B3%7D%20%20%5C%5C%20%20%3D%201.2%20%5Ctimes%2010%5E%7B%20-%205%7D%20%20%5C%3A%20m%20%5E%7B3%7D%20)
Mass of brick
= 151 g
= 151 ÷ 1000 kg
= 0.151 kg
Density of brick
= mass ÷ volume
![= \frac{0.151} {1.25 \times 10^{ - 5} } \\ = 12600 \: kg/ {m}^{3}](https://tex.z-dn.net/?f=%20%3D%20%20%5Cfrac%7B0.151%7D%20%7B1.25%20%5Ctimes%2010%5E%7B%20-%205%7D%20%7D%20%20%5C%5C%20%20%3D%2012600%20%5C%3A%20kg%2F%20%7Bm%7D%5E%7B3%7D%20)
(3 s.f.)
The bad smelling element is Sulfur, which smells like rotting eggs.
Answer:
Explanation:
Groundwater is stored in the open spaces within rocks and within unconsolidated sediments. Rocks and sediments near the surface are under less pressure than those at significant depth and therefore tend to have more open space. For this reason, and because it’s expensive to drill deep wells, most of the groundwater that is accessed by individual users is within the first 100 m of the surface. Some municipal, agricultural, and industrial groundwater users get their water from greater depth, but deeper groundwater tends to be of lower quality than shallow groundwater, so there is a limit as to how deep we can go.
Answer:
double replacement is the answer
Answer: d
Explanation: I got it right