If the heating is done on one small area on the top, there will be convection. If the heating is restricted to a small fraction of the heating area, then within that area the heating will go deeper than anywhere else on the surface. Then unheated area will have a shallower region of high temperature. Then some convection will occur in the deeper layers, causing some motion on top.
This happens quite a bit during welding. Convection is very significant in welding, even when the heating is from the top.
The formula you need is: heat= specific heat x mass x ΔT
specific heat= 0.46 j/g-C
mass= 100.0 grams
ΔT= 40.2 - 15.0= 25.2C
heat= (0.46) x (100.0) x (25.2)= 1159.2 joules or 1200 joules (rounded off)
<h2>Diethylether (DTH) andTetrahydrofuran (THF).</h2>
Explanation:
- Grignard reactions reacts with water forming alkanes.
- The water present causes the reagent to decompose rapidly.
- So, the solvents which are utilized in the experimental procedure to minimize exposure of the grignard reagents to air and/ormoisture are solvents such as anhydrous diethyl ether or tetrahydrofuran(THF), poly(tetramethylene ether) glycol (PTMG).
- The reason for the use of these solvents is the oxygen present in these solvents stabilizes the magnesium reagent.
- THF (Tetrahydrofuran) is a stable compound.
D baking soda and water because A B and C can all be separated while the baking soda will completely dissolve
Answer:
Cambrian
Explanation:
The fossil from the Cambrian is older than the one from the Triassic. This is because in the geologic time scale, the Cambrian is older than the Triassic.
- Absolute age of the Cambrian is between 541 - 484mya
- It is the first geological period in the Paleozoic era.
- The Triassic is the earliest period of the Mesozoic era
- It occurred about 237mya ago.
- Therefore, the fossils which corresponds to the Cambrian is the oldest.
