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.)
Answer: 4 molL-1
Explanation:
Detailed solution is shown in the image attached. The number of moles of NaCl is first obtained. Since the molarity must be in units of molL-1, the volume is divided by 1000 and the formula stated in the solution is applied and the answer is given to one significant figure.
In an ecosystem, the only true producers are autotrophic organisms like plants and bacteria. These organisms produce energy by converting the energy from the sun into simple sugars.
All of the other organisms in the food chain, like the fruit fly, are simply consuming the energy produced by the plants/bacteria and not actually making/producing energy from a new source.
In biological terms a cells main purpose is to survive but some important functions of cells are 1. Transports ( of molecules) 2. Chemical Reactions ( I.e Metabolism ) including energy conversion 3. reproduction hope this helps!
Answer: Sugar
Explanation: Because after photosynthesis (Carbon dioxide, water, and sunlight) react, they make two products. Glucose (A sugar) and Oxygen.
