<u>Answer:</u>
<em>Silver tarnishing as the silver metal reacts with sulphur is a chemical change.</em>
<u>Explanation:</u>
Tarnishing is the process of chemical change occurring on the surface of objects leading to corrosion or other defects on the surface. The remaining options like dilution, eroding is a physical change where the concentration of salt and rock particles will be decreased, respectively.
Similarly for soil drying also the concentration of water will be decreased leading to a physical change from wetty or dry soil.
But the last option which indicates tarnishing of silver metal on reaction with sulphur is a chemical process as the surface of silver metal will be reacting to sulphur and leads to lose of electrons which leads to corrosion of the surface or tarnishing of silver.
Answer/ explanation :
Protist can be multicellular or unicellular organisms
Plants are all multicellular and also exhibit cellular differentiation.
Protist can be autotroph, heterotrophic or decomposer
Plants are only autotrophs because they manufacture their own food through photosynthesis
Protists are microscopic, more diverse and abundant in nature
Plants are big and complex in nature
Nuclear DNA strands in plants are of higher complexity than those of protist
Plants require oxygen for cellular respiration process unlike protist which can be aerobic and some other species facultative anaerobic
Plants only can reproduce asexually through bulbs and tubers as in yam, potatoes while protists reproduce either sexually through meiosis or asexually through simple cell division.
The theoretical yield of I2 in the reaction would be 0.23 g
<h3>Theoretical yield</h3>
This refers to the stoichiometric yield of a reaction.
From the equation of the reaction:
Ca(IO3)2 + 10 KI + 12 HCl → 6 I2 + CaCl2 + 10 KCl + 6 H2O
The mole ratio of Ca(IO3)2 and I2 is 1: 6
Mole of 15.00 mL, 0.0100 M Ca(IO3)2 = 15/1000 x 0.0100
= 0.00015 mole
Equivalent mole of I2 = 0.00015 x 6
= 0.009 mole
mass of 0.0009 I2 = 0.0009 x 253.809
= 0.23 g
More on stoichiometric calculations can be found here: brainly.com/question/6907332
Answer:<span>d. 145 minutes
</span>
Half-life is the time needed for a radioactive to decay half of its weight. The formula to find the half-life would be:
Nt= N0 (1/2)^ t/h
Nt= the final mass
N0= the initial mass
t= time passed
h= half-life
If 25.0% of the compound decomposes that means the final mass would be 75% of initial mass. Then the half-live for the compound would be:
Nt= N0 (1/2)^ t/h
75%= 100% * (1/2)^ (60min/h)
3/4= 1/2^(60min/h)
log2 3/4 = log2 1/2^(60min/h)
0.41503749928 = -60min/h
h= -60 min / 0.41503749928= 144.6min
Using a calculator:
(2.568 x 5.8)/4.186 = 3.5581460…
= 3.56 (3sf)
You didn’t specify the correct number of significant figures needed.
