Given parameters:
Weight of hydrated sample = 20g
Temperature = 250°C
Weight after cooling = 16.5g
Unknown:
Weight of water lost from the sample = ?
Solution:
The weight of water lost from the sample;
Weight of water lost = Weight of hydrated sample - Weight of dry sample
Weight of water lost = 20g - 16.5g = 3.5g
% of water in the sample = 
Input parameters solve;
= 
=17.5%
The mass number of the daughter atom formed from the alpha decay of a certain radioactive atom that has 90 protons and 142 neutrons is 228.
<h3>What is alpha decay?</h3>
Alpha decay of a radioactive material is the release of an alpha particle that posseses mass number of 4 and atomic number of 2.
According to this question, a certain radioactive atom that has 90 protons and 142 neutron undergoes alpha decay. This means that the mass number of the daughter atom will be as follows:
Mass number of radioactive atom = 142 + 90 = 232
Mass number of daughter atom = 232 - 4 = 228
Therefore, the mass number of the daughter atom formed from the alpha decay of a certain radioactive atom that has 90 protons and 142 neutrons is 228.
Learn more about mass number at: brainly.com/question/4408975
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Answer:
3.018 x 10⁻⁶ M.
Explanation:
- Co(OH)₂ dissociates in solution according to the equation:
<em>Co(OH)₂ →</em> <em>Co²⁺ + 2OH⁻.</em>
<em></em>
<em>∵ Ksp = [Co²⁺][OH⁻]² = (s)(2s)² = 4s³.</em>
<em />
∴ 4s³ = 1.10 x 10⁻¹⁶.
∴ s³ = 1.10 x 10⁻¹⁶/4 = 2.75 x 10⁻¹⁷.
∴ s = ∛(2.75 x 10⁻¹⁷) = 3.018 x 10⁻⁶ M.
If i’m not mistaken it must be able to to design an experiment to test a hypothesis
Answer: 15.7 liters
Explanation: reaction is 2H2 + O2. -> 2H2O
Because all substance still are gases, volumes in
STP conditions are proportional to amount of moles.
Amount of water is same as Hydrogen. Also volume is same.
