A melting point of over 700 C and a density of less than 2 g/cm3 can be observed for many group 2 elements. In this group, the density increases on moving down the group, whereas the melting point increases upto calcium and then starts decreasing.
Calcium, symbol Ca is the element with melting point around 840 C and density of 1.55 g/cm3 which is closest to the specified data range .
Answer:
a) [H3O+] = 1.00 E-10 M ⇒ [OH-] = 1.0 E-4 M
b) [H3O+] = 1.00 E-4 M ⇒ [OH-] = 1.0 E-10 M
c) [H3O+] = 9.90 E-6 M ⇒ [OH-] = 1.0 E-9 M
Explanation:
- 14 = pH + pOH
- pH = - Log [H3O+]
a) [H3O+] = 1.00 E-10 M
⇒ pH = - Log(1.00 E-10) = 10
⇒ pOH = 14 - 10 = 4
⇒ 4 = - Log[OH-]
⇒ [OH-] = 1.0 E-4 M
b) [H3O+] = 1.00 E-4 M
⇒ pH = 4
⇒ pOH = 10
⇒ [OH-] = 1.0 E-10 M
c) [H3O+] = 9.90 E-6 M
⇒ pH = 5
⇒ pOH = 9
⇒ [OH-] = 1.0 E-9 M
Answer:
The answer is 30 g of sodium hydrocarbonate
Explanation:
This is a acid-base reaction, so in order to neutralise the spilled acid, the mol of spilled acid should be calculated.
M = n / V => n = M x V = 0.028 x 6.2 = 0.1736 mol
Since 1 mol of sulfuric acid generates 2 mol of H⁺, so the mole of H⁺ is 0.3472 mol or 0.35 mol with two significant figures.
To neutralized the acid, we need at least the same mole of base, so we need at least 0.35 mol of NaHCO₃, which can be converted to its mass at 29.4 g.
Since the answer need to be expressed in two significant figures and also need to make sure to neutralize all the acid, so we will use a little excess base. The answer is 30 g.
I would say B.HS(aq)+NiSO4(aq)
Answer:
1.17 grams of HCl can neutralize 2.7 grams sodium bicarbonate
Explanation:
Step 1: Data given
Mass of sodium bicarbonate = 2.7 grams
Step 2: The balanced equation
HCl + NaHCO3 ⇔ NaCl + H2O + CO2
Step 3: Calculate moles NaHCO3
moles NaHCO3 =2.7 g / 84 g/mol= 0.032 moles
Step 4: Calculate moles HCl
For 1 mol NaHCO3 we need 1 mol HCl
For 0.032 moles NaHCO3 = 0.032 moles HCl
Step 5: Calculate mass HCl
Mass HCl = moles HCl * molar mass HCl
mass HCl = 0.032 * 36.46 g/mol= 1.17 grams
1.17 grams of HCl can neutralize 2.7 grams sodium bicarbonate
