To answer this problem, we need to count the electrons in the given configuration. The complete configuration is 1s2 2s2 2p6 3s2 3p6. There are 2+2+6+2+6 equal to 18 electrons. We find next the element with an atomic number of 18. That element is noble gas argon.
Answer:
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Answer:
E = 29.7× 10⁻²⁰ j
Explanation:
Given data;
Frequency of light = 4.48 × 10¹⁴ Hz
Energy of photon = ?
Solution:
Formula:
E = h.f
E = energy of photon
h = planck's constant
f = frequency
E = h.f
E = 6.63 × 10⁻³⁴ Kg.m² /s × 4.48 × 10¹⁴ s⁻¹
E = 29.7× 10⁻²⁰ Kg.m²/s²
Kg.m²/s² = j
E = 29.7× 10⁻²⁰ j
Answer:
Alkali metal hydroxides can be used to test the identity of metals in certain salts. The colour of the precipitate will help identify the metal : Calcium hydroxide is soluble; no precipitate is formed.
Explanation:
To solve this problem, follow these steps;
- Obtain a balanced equation of the reaction and familiarize with the reactants and products.
- Find the number of moles of the reacting species since they are the known matter in terms of quantity.
- From the number of moles, determine the limiting reactant.
- The limiting reactant is the one given in short supply.
- Such reactant determines the extent of the reaction.
- Compare the moles of this specie to that of the products using the balanced equation.
- Obtain the mole of the desired product and find the mass or desired quantity.
- simply work from the known specie to the unknown
learn more:
Number of moles brainly.com/question/13064292
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