Answer:
128.4 g
Explanation:
Step 1: Given data
- Mass percent of element X in X(NO₃)₂: 52.55%
- Mass of the element X in the sample: 67.50 g
Step 2: Determine the total mass of the sample
The mass percent of element X in X(NO₃)₂ is 52.55%, that is, there are 52.55 g of X every 100 g of X(NO₃)₂. Then, the mass of X(NO₃)₂ that contains 67.50 g of X is:
67.50 g X × 100 g X(NO₃)₂/52.55 g X = 128.4 g X(NO₃)₂
Answer:
Magnesium is a naturally ubiquitous; (appearing & found evrywhere) element and has three naturally occurring stable isotopes, 24Mg, 25Mg and 26Mg, with relative abundance of 78.99%, 10.00% and 11.01%, respectively.
However, they differ only because a 24Mg atom has 12 neutrons in its nucleus, a 25Mg atom has 13 neutrons, and a 26Mg has 14 neutrons.
Explanation:
In this item, we are simply to find the ions that may bond and are able to form a formula unit. We are also instructed to give out their name. There are numerous possible combinations of ions to form a compound. Some answers are given in the list below.
1. Na⁺ , Cl⁻ , NaCl ---> sodium chloride (this is most commonly known as table salt)
2. C⁴⁺ , O²⁻ , CO₂ ---> carbon dioxide
3. Al³+ , Cl⁻ , AlCl₃ ----> aluminum chloride
4. Ca²⁺ , Cl⁻ , CaCl₂ ---> calcium chloride
5. Li⁺ , Br⁻ , LiBr ---> lithium bromide
6. Mg³⁺ , O²⁻ , Mg₂O₃ ----> magnesium oxide
7. K⁺ , I⁻ , KI ---> potassium iodide
8. H⁺ , Cl⁻ , HCl --> hydrogen chloride
9. H⁺ , Br⁻ , HBr ----> hydrogen bromide
10. Na⁺ , Br⁻ , NaBr ---> sodium bromide
To indicate whether the elements is basic or acid by changing of colour.(advantage)
can give out bad gas which can cause suffocate to the people.(disadvantage).
Answer:
The statement is false
Explanation:
Number of moles of alkene = 2.31 × 85/1000 = 0.196 moles
Number of moles of Br2 = 3.55 × 7.5/1000 = 0.0266 moles
Given that the reaction is 1:1
1 mole of alkene reacts with 1 mole of bromine
0.196 moles of alkene should react with 0.196 moles of bromine
Hence, to achieve 100%yield, 0.196 moles of bromine and not 25mmols of elemental bromine
