Answer:
A
Explanation:
If the Picture is a Desert showing reptiles like lizards and has cacti then it would be Dry and Sandy
Answer:
The diagram on the right. It has increments of 0.1 of a unit and therefore will provide a more precise measurement. The diagram on the right measures 88.4. In terms of the diagram on the left, a decimal answer cannot be determined because the increments are too large. Therefore the diagram on the left is less precise.
Answer:
The nonmetals in Groups 15, 16, and 17 form ions with charges of 3-, 2-, and 1-, respectively.
Explanation:
The elements of Group 18 (the noble gases) have a complete valence shell of eight electrons.
It is <em>easier</em> for the elements of Groups 15 to 17 <em>to</em> <em>gain</em> three, two, or one electron(s) to get a complete valence shell <em>than it is to lose</em> five, six, or seven valence electrons.
Thus, they form <em>negative ions</em> with charges of 3-, 2-, and 1-, respectively.
The charges <em>do not correspond</em> to the Group numbers of 15 to 17 or the old (pre-1990) Group numbers of 5A to 7A.
Answer:
i think protons and neutrons
Explanation:
im not sure tho
Using the ideal gas law equation, we can find the number of H₂ moles produced.
PV = nRT
Where P - pressure - 0.811 atm x 101 325 Pa/atm = 82 175 Pa
V - volume - 58.0 x 10⁻³ m³
R - universal gas constant - 8.314 Jmol⁻¹K⁻¹
T - temperature - 32 °C + 273 = 305 K
substituting these values in the equation,
82 175 Pa x 58.0 x 10⁻³ m³ = n x 8.314 Jmol⁻¹K⁻¹ x 305 K
n = 1.88 mol
The balanced equation for the reaction is as follows;
CaH₂(s) + 2H₂O(l) --> Ca(OH)₂(aq) + 2H₂(g)
stoichiometry of CaH₂ to H₂ is 1:2
When 1.88 mol of H₂ is formed , number of CaH₂ moles reacted = 1.88/2 mol
therefore number of CaH₂ moles reacted = 0.94 mol
Mass of CaH₂ reacted - 0.94 mol x 42 g/mol = 39.48 g of CaH₂ are needed
