Answer:
1. B. Ammonia and hexane will not dissolve because one molecule is polar and the other is non polar.
2. 1400 mL
Explanation:
In chemistry, like dissolve like! Ammonia is a polar molecule having a significant dipole moment owing to its three N-H bonds. On the other hand, hexane is a purely non-polar hydrocarbon hence the two substances can never dissolve in each other.
From the dilution formula;
C1V1=C2V2
C1= Initial concentration of the solution
V1 = Initial volume of the solution
C2 = Final concentration of the solution
V2= Final volume of the solution
2.8 M * 750.0 mL = 1.5 M * V2
V2 = 2.8 M * 750.0 mL/1.5 M
V2 = 1400 mL
If magnesium and nickel were used as electrodes to construct an electrochemical cell like the one shown at right, which metal would form the anode and which the cathode?
anode:
cathode:
Answer:
anode: magnesium
cathode: nickel
Explanation:
edg. 2021
A sample containing 0.75 moles of CO2 would contain how many atoms?
Answer:4.5 ×10^22)
Explanation:
no. of particles =no. of mole×avogadro's number of particles no. of particles =0.75×6.02×10^23 no. of particles =4.5 ×10^22
Can someone tell me if these are right? I am supposed to be decoding this for my escape room but it seems to be wrong.
Answer:
Q1 is A.
Q2 is right
Q3 is D.....I dont
really know about this one
Q4 is right
The number of protons is equal to
a the number of neutrons.
b the atomic mass.
c the number of electrons.
d the atomic number.
Answer:
c the number of electrons
Explain how a long-term environmental change can lead
to the development of a new species.( its a paragraph
Answer:
Humans are modifying the world in many ways, and not all of them for the better. The changes we cause are often severe challenges to animals, plants and microbes in nature, from the introduction of pathogens or exotic invasive species to adding toxic substance or excessive nutrients, or causing climatic change. Often several changes occur at once. Nelson Hairston's lab focuses on freshwater environments, especially lakes and ponds, where some of the species present respond to environmental change with decreases in their numbers, even to the point of extinction, while others may benefit to excess, becoming so dominant that they present problems, as in the case of harmful algal blooms stimulated by nutrient enrichment or climate warming. Hairston's lab studies how individual species, food webs, and whole ecosystems are altered when the environment changes.
One way that some freshwater organisms respond to environmental change is to evolve rapidly. A marked change in the environment favors some characteristics of plants, animals and microbes over others. These character differences are often genetically based so that favored characteristics may increase in the next generation. The shorter the generation time, the faster this evolutionary change can occur. For example, tiny but abundant plankton, eaten by fish and other larger animals, can become adapted to the changed environment within a few years because their generation time is only a few days. Hairston's lab has shown that planktonic "water fleas" (Daphnia), major consumers of suspended algae in lakes, evolved to be tolerant of harmful algae within a decade of the appearance of blooms. This rapid evolution (termed "evolutionary rescue" in conservation biology) raises many intriguing questions, for all environments, not just freshwater: To what extent can we rely on species adapting rather than going extinct when their environment changes? How does the evolution of a species that plays a critical ecological role alter the interactions it has with other species, and the functioning of the entire ecosystem?