You can use the displacement method or the eureka can so basically in the displacement can what you have to do is to put some water into a measuring cylinder and measure its volume before adding the irregular shaped object and then measuring the level of water which had been displaced and then eureka can you can check online
You would know a decomposition reaction occurred if the reactants separated. For example from AB → A+B.
Now if you look at your options only 1 works out for that equation. Letter A.
From the compound K2CO3 it split up to K2O +CO2
It cannot be letter B because synthesis/combination occurred. The same goes for letter C. Letter D, single displacement occurred.
Again, the answer is A.
The amount of gold in decigrams if 450 micrograms is needed is 4.5 × 10-³ decigrams.
<h3>How to convert micrograms to decigrams?</h3>
According to this question, 450 micrograms of a sample of gold is needed but we only have a mass balance that measures in decigrams.
This means that we are to convert the amount of gold you need to decigrams by comparing the exponents.
The conversion factor of micrograms to decigrams is as follows:
1 micrograms = 1 × 10-⁵ decigrams
This means 450 micrograms is equivalent to 450 × 1 × 10-⁵ = 4.5 × 10-³ decigrams
Therefore, the amount of gold in decigrams if 450 micrograms is needed is 4.5 × 10-³ decigrams.
Learn more about decigrams at: brainly.com/question/6869599
#SPJ1
Answer:
42 grams
Explanation:
you multiply the value by 1000 to get your answer