The suggestion is to prevent a puddle of the liquid present in the sample from forming or from it leaking on to the surface on which it is placed. For example, if precipitates of a solid are removed from water and then placed on filter paper to dry, the water will soak into the filter paper and then leak on to the counter on which it is placed. If this precipitate were placed in a watch glass or weighing paper, the water would only evaporate and would not contaminate the sample.
Have a different number of protons
Answer:
True
Explanation:
Ionic bonds are formed by complete transfer of electronic from one to another atoms. The metals are electron donor and non metal are the electron accepter.
Consider the example of sodium chloride. Sodium is metal and chlorine is non metal. Sodium is present in group one and have one valence electron. It loses one electron and get stable electronic configuration.
While chlorine is present in group 7A and have seven valence electron. It require one more electron to complete the octet. Thus hen sodium and chlorine the electron lose by sodium is accepted by chlorine and form ionic compound.
The compound having ionic bonds generally have moderate to high boiling points and melting point because of greater electrostatic interaction. Their electrical conductivity are high and these minerals tend to dissolve in water.
Water vapor possesses latent energy. this form of heat energy is the force that drives the water cycle in nature.
Answer:
B
Explanation:
When a phospholipid is found in a sphere of water, the hydrophilic head is expected to point towards the water while the hydrophobic tail will point away from the water.
The term hydrophilic means water loving, So it is expected that the hydrophilic head will move towards water molecules at it has affinity for water molecules.
The opposite is the case for the hydrophobic tail. The hydrophobic tail moves away from water molecules
What these cases suggest is that both regions are acting base on their chemical make up. While the hydrophilic head contains molecules which are capable of interacting and bonding with water molecules, the hydrophobic tail contains strictly non polar molecules which are not capable of water interaction. Hence the interactions a phospholipid has with water is through its head region